choose random text between constant string.. using awk?


 
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Old 02-14-2010
Hi.
Quote:
Originally Posted by ironmask2004
but you need to know how muche recoreds you have insaide the fill to generate a random number betwwen 1 and NUM Of Rec !!!
If one is willing to devote the time and effort, the reservoir sampling method allows one to extract a random sample in a single pass through a file. A brief explanation along with a python and perl code can be found at Program-o-Babble: Reservoir Sampling Algorithm in Python and Perl among many other places.

Best wishes ... cheers, drl
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mlib_ImageColorRGB2CIEMono(3MLIB)			    mediaLib Library Functions				 mlib_ImageColorRGB2CIEMono(3MLIB)

NAME
mlib_ImageColorRGB2CIEMono - RGB to monochrome conversion SYNOPSIS
cc [ flag... ] file... -lmlib [ library... ] #include <mlib.h> mlib_status mlib_ImageColorRGB2CIEMono(mlib_image *dst, const mlib_image *src); DESCRIPTION
The mlib_ImageColorRGB2CIEMono() function performs a conversion from a red/green/blue to a monochromatic image. The source image must be a three-channel image. The destination image must be a single-channel image. It uses the following equation: dst[x][y][0] = 0.2125*src[x][y][0] + 0.7154*src[x][y][1] + 0.0721*src[x][y][2] PARAMETERS
The function takes the following arguments: dst Pointer to destination image. src Pointer to source image. RETURN VALUES
The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Committed | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
mlib_ImageColorRGB2CIEMono_Fp(3MLIB), mlib_ImageColorRGB2Mono(3MLIB), mlib_ImageColorRGB2Mono_Fp(3MLIB), attributes(5) SunOS 5.11 2 Mar 2007 mlib_ImageColorRGB2CIEMono(3MLIB)