| 释义 |
pi
PIabbr. private investigator
pi 1 P0280900 (pī)n.1. (also pē) The 16th letter of the Greek alphabet. See Table at alphabet.2. Mathematics A transcendental number, approximately 3.14159, represented by the symbol π, that expresses the ratio of the circumference to the diameter of a circle and appears as a constant in many mathematical expressions.
[Late Greek pī, from Greek pei, of Phoenician origin; see p in Semitic roots.]
pi 2 also pie P0280900 (pī)Printing n. pl. pis also pies An amount of type that has been jumbled or thrown together at random.v. pied (pīd), pi·ing, pies also pied, pie·ing, pies v.tr. To jumble or mix up (type).v.intr. To become jumbled.
[Origin unknown.]pi (paɪ) n, pl pis1. (Letters of the Alphabet (Foreign)) the 16th letter in the Greek alphabet (Π, π), a consonant, transliterated as p2. (Mathematics) maths a transcendental number, fundamental to mathematics, that is the ratio of the circumference of a circle to its diameter. Approximate value: 3.141 592…; symbol: π[C18 (mathematical use): representing the first letter of Greek periphereia periphery]
pi (paɪ) or pien, pl pies1. (Printing, Lithography & Bookbinding) a jumbled pile of printer's type2. a jumbled mixturevb (tr) , pies, piing, pied, pies, pieing or pied3. (Printing, Lithography & Bookbinding) to spill and mix (set type) indiscriminately4. to mix up[C17: of uncertain origin]
pi (paɪ) adjslang Brit short for pious2, pious3
PI abbreviation for 1. (Placename) Philippine Islands 2. (Law) private investigator pi1 (paɪ)
n., pl. pis. 1. the 16th letter of the Greek alphabet (Π, π). 2. a. the letter π, used as the symbol for the ratio of the circumference of a circle to its diameter. b. the ratio itself: 3.14159 +. [1835–45; < Greek pî, peî; used in math to represent Greek periphérion periphery] pi2 or pie (paɪ)
n., pl. pies, n. 1. printing type mixed together indiscriminately. 2. any confused mixture; jumble. v.t. 3. to jumble (printing type). 4. to mix up; jumble. [1650–60; orig. uncertain] P.I. Philippine Islands. pi (pī) An irrational number that has a numerical value of 3.14159265359... and is represented by the symbol π. It expresses the ratio of the circumference to the diameter of a circle and appears as a constant in many mathematical expressions.pi
Past participle: pied
Gerund: piing
| Present | I piyou pihe/she/it pieswe piyou pithey pi |
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| Preterite | I piedyou piedhe/she/it piedwe piedyou piedthey pied |
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| Present Continuous | I am piingyou are piinghe/she/it is piingwe are piingyou are piingthey are piing |
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| Present Perfect | I have piedyou have piedhe/she/it has piedwe have piedyou have piedthey have pied |
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| Past Continuous | I was piingyou were piinghe/she/it was piingwe were piingyou were piingthey were piing |
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| Past Perfect | I had piedyou had piedhe/she/it had piedwe had piedyou had piedthey had pied |
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| Future | I will piyou will pihe/she/it will piwe will piyou will pithey will pi |
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| Future Perfect | I will have piedyou will have piedhe/she/it will have piedwe will have piedyou will have piedthey will have pied |
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| Future Continuous | I will be piingyou will be piinghe/she/it will be piingwe will be piingyou will be piingthey will be piing |
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| Present Perfect Continuous | I have been piingyou have been piinghe/she/it has been piingwe have been piingyou have been piingthey have been piing |
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| Future Perfect Continuous | I will have been piingyou will have been piinghe/she/it will have been piingwe will have been piingyou will have been piingthey will have been piing |
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| Past Perfect Continuous | I had been piingyou had been piinghe/she/it had been piingwe had been piingyou had been piingthey had been piing |
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| Conditional | I would piyou would pihe/she/it would piwe would piyou would pithey would pi |
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| Past Conditional | I would have piedyou would have piedhe/she/it would have piedwe would have piedyou would have piedthey would have pied |
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pi(") Symbol and name representing the ratio of a circle’s circumference to its diameter. Its value is approximately 3.14.Thesaurus| Noun | 1. pi - the ratio of the circumference to the diameter of a circle; approximately equal to 3.14159265358979323846...transcendental number - an irrational number that is not algebraic | | 2. PI - someone who can be employed as a detective to collect informationprivate detective, private eye, private investigator, shamus, sherlock, operativedetective - an investigator engaged or employed in obtaining information not easily available to the publichotel detective, house detective, house dick - a private detective employed by a hotel or retail storeinquiry agent - a private detectivestore detective - a private detective employed by a merchant to stop pilferage | | 3.PI - the scientist in charge of an experiment or research projectprincipal investigatorscientist - a person with advanced knowledge of one or more sciences | | 4.pi - the 16th letter of the Greek alphabetGreek alphabet - the alphabet used by ancient Greeksalphabetic character, letter of the alphabet, letter - the conventional characters of the alphabet used to represent speech; "his grandmother taught him his letters" | | 5.PI - an antiviral drug used against HIV; interrupts HIV replication by binding and blocking HIV protease; often used in combination with other drugsprotease inhibitorantiviral, antiviral agent, antiviral drug - any drug that destroys virusesdrug cocktail, HAART, highly active antiretroviral therapy - a combination of protease inhibitors taken with reverse transcriptase inhibitors; used in treating AIDS and HIVCrixivan, indinavir - a protease inhibitor (trade name Crixivan) used for treating HIVnelfinavir, Viracept - a protease inhibitor (trade name Viracept) used in treating HIV usually in combination with other drugsNorvir, ritonavir - a protease inhibitor (trade name Norvir) used in treating HIVInvirase, saquinavir - a weak protease inhibitor (trade name Invirase) used in treating HIV |
Translationspi
pi, in mathematics, the ratio of the circumference of a circle to its diameter. The symbol for pi is π. The ratio is the same for all circles and is approximately 3.1416. It is of great importance in mathematics not only in the measurement of the circle but also in more advanced mathematics in connection with such topics as continued fractions, logarithms of imaginary numbers, and periodic functions. Throughout the ages progressively more accurate values have been found for π; an early value was the Greek approximation 3 1-7, found by considering the circle as the limit of a series of regular polygons with an increasing number of sides inscribed in the circle. About the mid-19th cent. its value was figured to 707 decimal places and by the mid-20th cent. an electronic computer had calculated it to 100,000 digits. Although it has now been calculated to some 2.6 trillion digits, the exact value of π cannot be computed. It was shown by the German mathematician Johann Lambert in 1770 that π is irrational and by Ferdinand Lindemann in 1882 that π is transcendental; i.e., cannot be the root of any algebraic equation with rational coefficients. The important connection between π and e, the base of natural logarithms, was found by Leonhard Euler in the famous formula eiπ=−1, where i=√−1.Pi π, a letter of the Greek alphabet used in mathematics to denote a particular irrational number—the ratio of the circumference to the diameter of a circle. The symbol was probably adopted from the Greek word for “circumference,” or “periphery.” Although it came into general use after a paper by L. Euler in 1736, it was first used by the British mathematician W. Jones in 1706. Like all irrational numbers, π is an infinite nonrepeating decimal fraction: π = 3.141592653589793238462643… The requirements of practical calculations involving circles and circular solids long ago made it necessary to find approximations of π by rational numbers. In the second millennium B.C., ancient Egyptian computations of the area of a circle made use of the approximation π ≈ 3, or, more precisely, π ≈ (16/9)2= 3.16049.… In the third century B.C., Archimedes found, by comparing the circumference of a circle to regular inscribed and circumscribed polygons, that π is between the values 
The second value is still used in calculations that do not require great accuracy. In the second half of the fifth century, the Chinese mathematician Tsu Ch’ung-chih obtained the approximation 3.1415927, which much later (16th century) was also found in Europe. This approximation is exact for the first six decimal places. The search for a more exact approximation of π continued in later periods. For example, in the first half of the 15th century, al-Kashi calculated π to 17 places. In the early 17th century, the Dutch mathematician Ludolph van Ceulen obtained 32 places. For practical needs, however, it is sufficient to have values for π and the simplest expressions in which π occurs to only a few decimal places; reference works usually give four- to seven-place approximations for π, 1/π, π2, and log π. The number π appears not only in the solution of geometric problems. Since the time of F. Vieta (16th century), the limits of certain arithmetic sequences generated by simple rules have been known to involve π. An example is Leibniz’ series (1673-74) 
This series converges extremely slowly. There exist series for calculating π that converge much more rapidly. An example is the formula 
where the values of the arc tangents are calculated by means of the series 
The formula was used in 1962 for a computer calculation of π to 100,000 places. This type of calculation is of interest in connection with the concept of random and pseudorandom numbers. Statistical processing has shown that this set of 100,000 digits exhibits many features of a random sequence. The possibility of a purely analytic definition of π is of fundamental importance for geometry. Thus, in non-Euclidean geometry π also occurs in some formulas but is no longer the ratio of the circumference to the diameter of a circle, for the ratio is not a constant in non-Euclidean geometry. The arithmetic nature of π was finally clarified by analytic means, among which a crucial role was played by the remarkable Euler formula e2πi = 1, where e is the base of the natural system of logarithms and  . At the end of the 18th century, J. H. Lambert and A. M. Legendre proved that π is irrational. In 1882 the German mathematician F. Lindemann showed it to be transcendental—that is, it cannot satisfy any algebraic equation with integral coefficients. The Lindemann theorem conclusively established that the problem of squaring the circle cannot be solved by means of a compass and straightedge. REFERENCESO kvadrature kruga (Arkhimed, Giuigens, Lambert, Lezhandr): Sprilozheniem istorii voprosa…, 3rd ed. Moscow-Leningrad, 1936. (Translated from German.)
Shanks, D., and J. W. Wrench. “Calculation of π to 100,000 Decimals.” Mathematics of Computation, 1962, vol. 16, no. 77.pi[pī] (mathematics) The irrational number which is the ratio of the circumference of any circle to its diameter; an approximation is 3.14159. Symbolized π. pi1. the 16th letter in the Greek alphabet (Π, π), a consonant, transliterated as p 2. Maths a transcendental number, fundamental to mathematics, that is the ratio of the circumference of a circle to its diameter. Approximate value: 3.141 592…; symbol: π PIAn interface between Prolog application programs and theX Window System that aims to be independent from theProlog engine, provided that it has a Quintus foreign function interface (e.g. SICStus and YAP). It is mostlywritten in Prolog and is divided in two libraries: Edipo -the lower level interface to the Xlib functions; andYtoolkit - the higher level user interface toolkit.
ftp://ftp.ncc.up.pt/pub/prolog/ytoolkit.tar.Z.
E-mail: Ze' Paulo Leal .piThe 16th letter of the Greek alphabet. It is used as a symbol for the ratio of the circumference of a circle to its diameter, which is 3.141592653, commonly rounded to 3.14. Perhaps no other number has been more pondered, examined and calculated than pi. Circa 1650 B.C., the ratio was computed by an Egyptian scribe, and the number was recorded as 3.16049 in the Rhind Papyrus. The writings described how to create a square area the same size as a circle.
The Exact Value of Pi
Over the years, pi, which was named some 3,000 years later, has been calculated numerous times to the maximum decimal place that humans and calculating devices could take it. In 1596, it was calculated to 32 decimal places and up to 127 places by 1719. In 1949, the ENIAC took 70 hours to yield 2,037 digits. However, in 1997, a Hitachi mainframe computed pi to 51.5 billion digits in 29 hours. The bottom line is that the absolutely exact value of pi cannot be computed.
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pi
π1. The 16th letter of the Greek alphabet, pi. 2. Symbol for the ratio of the circumference of a circle to its diameter, approximately 3.14159; symbol for osmotic pressure (Π).
PiSymbol for inorganic orthophosphate (should not be used when covalently linked to another moiety).
PIAbbreviation for Periodontal Index.
PiAbbreviation for inorganic phosphate.
pIThe pH value for the isoelectric point of a given substance.
pi (π, Π), (pī), 1. The 16th letter of the Greek alphabet. 2. (Π). Symbol for osmotic pressure; in mathematics, symbol for the product of a series. 3. (π). Symbol for the ratio of the circumference of a circle to its diameter (approximately 3.14159). 4. Symbol for pros. PI Abbreviation for:
package insert
pain intensity
pancreatic insufficiency
parallel imports
pars intermedia
paternity index
Pearl Index
performance indicator, see there
perfusion imaging
peripheral iridectomy
phosphatidyl inositol
physically impaired
physiologic index
pituitary
plaque inhibition
poison ivy
post-implantation
post-infection
post-injection
post-inoculation
post-irradiation
post-ischaemic
present illness
primary infection
principal investigator
product information
prognostic index
proliferation index
protease inhibitor
pulmonary index
pulmonary infarction
pulmonary insufficiency
pulse inversionπ Greek, lower case, pi.
Π Abbreviation for osmotic pressure; pi.
PiAbbreviation for inorganic orthophosphate.
PI Abbreviation for Periodontal Index.
pI Abbreviation for isoelectric point.
pi (π, Π) (pī) 1. The 16th letter of the Greek alphabet (π, Π). 2. Osmotic pressure (Π). 3. mathematics Symbol for the product of a series (Π). 4. Symbol for the ratio of the circumference of a circle to its diameter (approximately 3.14159265) (π). Π Abbreviation for osmotic pressure.
PI Abbreviation for Periodontal Index.
pI Abbreviation for isoelectric point.
pi , π (pī) 1. The 16th letter of the Greek alphabet. 2. (Π). Symbol for osmotic pressure; in mathematics, symbol for the product of a series. LegalSeeIndexFinancialSeePiePI
| Acronym | Definition |
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| PI➣Private Investigator | | PI➣Politically Incorrect | | PI➣Per Inquiry | | PI➣[not an acronym] name for Greek symbol representing the ratio of the circumference of a circle to its diameter; approximately 3.1416 | | PI➣Pisa (Tuscany, Italy) | | PI➣Plug In | | PI➣Product Information | | PI➣Private Investigations (movie) | | PI➣Process Integration | | PI➣Phase I (clinical studies) | | PI➣Principal Investigator | | PI➣Public Information | | PI➣Program Improvement | | PI➣Process Improvement | | PI➣Personal Injury (legal) | | PI➣Phosphate (Inorganic) | | PI➣Protease Inhibitor | | PI➣Professional Indemnity (insurance coverage) | | PI➣Poison Ivy | | PI➣Plant Industry (Commonwealth Scientific and Industrial Research Organisation; Australia) | | PI➣Package Insert (medications) | | PI➣Program Information | | PI➣Performance Improvement | | PI➣Piauí (Brazilian state) | | PI➣Post Intelligencer (newspaper, Seattle, Washington) | | PI➣Processing Instruction | | PI➣Polyimide (polymer) | | PI➣Punto Informatico | | PI➣Per Inch | | PI➣Point of Intersection | | PI➣Point of Impact | | PI➣Policy and International Affairs | | PI➣Pleasure Island (Disney World) | | PI➣Pinellas (plant; Florida) | | PI➣Prescribing Information (medication) | | PI➣Philadelphia Inquirer (newspaper) | | PI➣Paging (assembly language ASM51 assembler control) | | PI➣Performance Index | | PI➣Privacy Information (UK) | | PI➣Pinneberg (auto license plate) | | PI➣Petroleum Institute | | PI➣PCNA (Proliferating Cell Nuclear Antigen) Labeling Index | | PI➣Performance Indicator | | PI➣Public Involvement (various locations) | | PI➣Parental Involvement (various organizations) | | PI➣Police Interceptor | | PI➣Personal Inspection | | PI➣Privacy International (human rights group) | | PI➣Proprietary Information | | PI➣Pulse Induction | | PI➣Physik Instrumente | | PI➣Plasticity Index | | PI➣Please Inquire | | PI➣Program Instructions | | PI➣Presque Isle (Michigan) | | PI➣Propidium Iodide | | PI➣Point of Inflection (engineering) | | PI➣Physikalisches Institut (German: Institute of Physics) | | PI➣Proportional-Integral (controller) | | PI➣Primer Impacto (TV show) | | PI➣Isoelectric Point (chemistry) | | PI➣Process Industries | | PI➣Pulmonary Infection (lungs) | | PI➣Physical Inventory | | PI➣Plaque Index (oral hygiene) | | PI➣Predictive Index | | PI➣Persistently Infected | | PI➣Periodic Inspection | | PI➣Plant Information (real-time software products such as SCADA) | | PI➣PhotoImpact (digital imaging software) | | PI➣Propriedade Intelectual (Intellectual Property, Brazil) | | PI➣Project Impact (various organizations) | | PI➣Premature Infant | | PI➣Pacific Institute | | PI➣Penile Implant | | PI➣Blood Clotting | | PI➣Personal Investigator (less common) | | PI➣Perpetual Inventory | | PI➣Parris Island | | PI➣Planet Internet | | PI➣Preliminary Injunction | | PI➣Polynomial Identity (mathematics) | | PI➣Photo Interpretation | | PI➣Polyisocyanurate (rigid foam contruction material) | | PI➣Physics International | | PI➣Passes Intercepted (soccer) | | PI➣Platform Integration (various organizations) | | PI➣Power Integrations | | PI➣Perimeter Institute for Theoretical Physics | | PI➣Pass Interference (football) | | PI➣Pandemic Influenza | | PI➣Policy Issuance (insurance) | | PI➣Private Idaho | | PI➣Program Introduction (various organizations) | | PI➣Praktische Informatik (German: Applied Informatics) | | PI➣Primary Immunodeficiency | | PI➣Paedagogisches Institut (Vienna, Austria) | | PI➣Program Integrity | | PI➣Physically Impaired | | PI➣Program Increment | | PI➣Process & Instrumentation | | PI➣Peripheral Iridotomy | | PI➣Ponderal Index | | PI➣Philippine Islands (slang) | | PI➣Project Inspector (various locations) | | PI➣Performance Insight (Oracle) | | PI➣Personal Identifier | | PI➣Pulmonary Insufficiency (cardiac measurement) | | PI➣Pentium I (Intel) | | PI➣Paternity Index | | PI➣Parallel Interface | | PI➣Plant Integrity | | PI➣Position Indicator | | PI➣Public Intoxication (law enforcement) | | PI➣Purchase Intent (marketing) | | PI➣Pulsatility Index | | PI➣Product Integration | | PI➣Power Interface | | PI➣Pearl Islands (Hawaii) | | PI➣Physician Information | | PI➣Product Improvement | | PI➣Profitability Index | | PI➣Program Index | | PI➣Population Institute | | PI➣Plouffe's Inverter | | PI➣Postinjection | | PI➣Pressure Indicator (industrial control description) | | PI➣Pacific Internet (Internet Service Provider) | | PI➣Post Inoculation | | PI➣Platform Initialization (Specification) | | PI➣Precision Instrument | | PI➣Productivity Index (oil and gas well performance) | | PI➣Paranormal Investigator | | PI➣Provider Independent (IP address space assigned by IANA) | | PI➣Program Identification | | PI➣Production Insurance | | PI➣Photo Interpreter | | PI➣Proforma Invoice | | PI➣Programmed Instruction | | PI➣Proyectos Industriales | | PI➣Project Identification (number) | | PI➣Profitabilty Improvement | | PI➣Prediction Interval | | PI➣Packet Interface | | PI➣Partner Institution | | PI➣Productivity Increase | | PI➣Page Impression (Internet advertising) | | PI➣Product Integrity | | PI➣Priority Inheritance | | PI➣Protocol Interpreter | | PI➣Paper Insulated | | PI➣International Protocol | | PI➣Prison Industry | | PI➣Perlite Institute (Staten Island, NY) | | PI➣Point Initiating | | PI➣Program Interruption | | PI➣Paranoid Ideation | | PI➣Panicle Initiation | | PI➣Phosphorus Index | | PI➣Pursuit Inc. | | PI➣Paperi-Insinöörit (Finnish: Paper Engineers) | | PI➣Par Intérim (French: Deputizing) | | PI➣Parameter Identifier (ITU-T) | | PI➣Istiqlal Party (Independence Party, Morocco) | | PI➣Particular Integral | | PI➣Payload Integrator | | PI➣Perforated Initials (philately) | | PI➣Patente de Invenção (Patent, Brazil) | | PI➣Photographic Interpreter | | PI➣Prime Implicant | | PI➣Primary Injection | | PI➣Projets Individuels | | PI➣Portable Interceptors | | PI➣Popcorn Institute (Chicago, IL) | | PI➣Pigeon Trainer (US Navy) | | PI➣Primary Investigations | | PI➣Purchasing Instruction | | PI➣Pusat Informasi (Indonesian: Information Center) | | PI➣Précompte Immobilier (French: tax on real estate) | | PI➣Parents for Inclusion | | PI➣Price Integrity | | PI➣Paradigm Infinitum (Singapore) | | PI➣Program Isolation (IBM) | | PI➣Physicist Interface | | PI➣Praendex Incorporated (Wellesley, MA) | | PI➣Principal Insured | | PI➣PrintImage International | | PI➣Parameter Indicator | | PI➣Prospective Internationale | | PI➣Perceptually Impaired | | PI➣Pulse Inverter | | PI➣Perception Immédiate (French) | | PI➣Parent Initial | | PI➣Projector Infantry | | PI➣Psykoterapiinstitut (Stockholm, Sweden) | | PI➣Paducah & Illinois Railroad | | PI➣Procurement Instruction | | PI➣Page Interleaving | | PI➣Professional Informant | | PI➣Psicología Integrada (Portugese) | | PI➣Ionized Phosphorus | | PI➣Proto-I.jo | | PI➣Passive Intercept | | PI➣Pampers Institute (UK) | | PI➣Profil Infirmier | | PI➣Probationary Instructor | | PI➣Preliminary Investigation Coordinator (Canada) | | PI➣Pallidum Internum |
pi
Words related to pinoun the ratio of the circumference to the diameter of a circleRelated Wordsnoun someone who can be employed as a detective to collect informationSynonyms- private detective
- private eye
- private investigator
- shamus
- sherlock
- operative
Related Words- detective
- hotel detective
- house detective
- house dick
- inquiry agent
- store detective
noun the scientist in charge of an experiment or research projectSynonymsRelated Wordsnoun the 16th letter of the Greek alphabetRelated Words- Greek alphabet
- alphabetic character
- letter of the alphabet
- letter
noun an antiviral drug used against HIVSynonymsRelated Words- antiviral
- antiviral agent
- antiviral drug
- drug cocktail
- HAART
- highly active antiretroviral therapy
- Crixivan
- indinavir
- nelfinavir
- Viracept
- Norvir
- ritonavir
- Invirase
- saquinavir
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