Documentation
¶
Overview ¶
Package pi calculates the nth and 8 following fractional decimal digits of pi using a Bailey-Borwein-Plouffe algorithm (see https://wikipedia.org/wiki/Bailey%E2%80%93Borwein%E2%80%93Plouffe_formula). This allows any arbitrary fractional digit of pi to be calculated independently of the preceding digits albeit with longer calculation times as the value of n increases because of the need to calculate prime numbers of increasing value.
NOTE 1: This package is intended to be used in distributed computing and cloud scaling demos, and does not guarantee accuracy or efficiency of calculated fractional digits.
NOTE 2: The algorithms used invMod, powMod, and BPPDigits are based on the work of Fabrice Bellard (original source code published at https://bellard.org/pi/pi.c).
Example ¶
package main
import (
"fmt"
"log"
"os"
"github.com/go-logr/stdr"
pi "github.com/memes/pi/v2"
)
func main() {
// Enable verbose library logging to standard library logger via go-logr/stdr
_ = stdr.SetVerbosity(1)
pi.Logger = stdr.New(log.New(os.Stdout, "", log.Lshortfile))
// Calculate the first 9 decimal digits of pi
digits := pi.BBPDigits(0)
fmt.Printf("The first 10 digits of pi are: 3.%s\n", digits)
}
Output: pi.go:112: "level"=1 "msg"="BBPDigits: enter" "n"=0 pi.go:174: "level"=1 "msg"="BBPDigits: exit" "n"=0 "result"="141592653" The first 10 digits of pi are: 3.141592653
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( // The package logr.Logger instance to use. //nolint:gochecknoglobals // Allow package consumers to set the logger Logger = logr.Discard() // The number of Miller-Rabin rounds to use in FindNextPrime when // determining if an integer is probabilistically a prime. A value of // zero will apply a Baillie-PSW only test and requires Go 1.8+. //nolint:gochecknoglobals // Allow package consumers to override MillerRabinRounds = 0 )
Functions ¶
func BBPDigits ¶
Implements a BBP spigot algorithm to determine the nth and 8 following fractional decimal digits of pi at the specified zero-based offset.
Example ¶
package main
import (
"fmt"
pi "github.com/memes/pi/v2"
)
func main() {
// Print the first 100 digits of pi using a default calculator
fmt.Printf("The first 100 digits of pi are: 3.")
for n := uint64(0); n < 99; n += 9 {
fmt.Print(pi.BBPDigits(n))
}
fmt.Println()
}
Output: The first 100 digits of pi are: 3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067
func FindNextPrime ¶
Return the next largest prime number that is greater than n.
Example ¶
package main
import (
"fmt"
pi "github.com/memes/pi/v2"
)
func main() {
// Find the first prime number after 10,000
nextPrime := pi.FindNextPrime(10000)
fmt.Printf("The first prime number greater than 10000 is %d\n", nextPrime)
}
Output: The first prime number greater than 10000 is 10007
Types ¶
This section is empty.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
cmd
|
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pi
This package contains a gRPC client and server to demonstrate use of library in a distributed environment.
|
This package contains a gRPC client and server to demonstrate use of library in a distributed environment. |
|
pkg
|
|
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cache
Package cache defines a common interface for cache implementations that can be used by PiService implementations.
|
Package cache defines a common interface for cache implementations that can be used by PiService implementations. |
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client
Package client implements a gRPC client implementation that satisfies the PiServiceClient interface requirements with optional OpenTelemetry metrics and traces.
|
Package client implements a gRPC client implementation that satisfies the PiServiceClient interface requirements with optional OpenTelemetry metrics and traces. |
|
generated
Package generated contains the generated code for gRPC client and server stubs, and an OpenAPIv2 (swagger) JSON declaration, from protobuf source(s).
|
Package generated contains the generated code for gRPC client and server stubs, and an OpenAPIv2 (swagger) JSON declaration, from protobuf source(s). |
|
server
Package server implements a gRPC server (and optional REST gateway) implementation that satisfies the PiServiceClient interface requirements, with optional OpenTelemetry metrics and traces.
|
Package server implements a gRPC server (and optional REST gateway) implementation that satisfies the PiServiceClient interface requirements, with optional OpenTelemetry metrics and traces. |