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NAME | C SYNOPSIS | DESCRIPTION | NOTES | SEE ALSO | COLOPHON |
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PMNUMBERSTR(3) Library Functions Manual PMNUMBERSTR(3)
pmNumberStr, pmNumberStr_r - fixed width output format for numbers
#include <pcp/pmapi.h>
const char *pmNumberStr(double value);
char *pmNumberStr_r(double value, char *buf, int buflen);
cc ... -lpcp
pmNumberStr returns the address of a 8-byte buffer that holds a null-
byte terminated representation of value suitable for output with
fixed width fields. The pmNumberStr_r function does the same, but
stores the result in a user-supplied buffer buf of length buflen,
which should have room for at least 8 bytes.
The value is scaled using multipliers in powers of ``one thousand''
(the decimal ``kilo'') and has a bias that provides greater precision
for positive numbers as opposed to negative numbers.
The format depends on the sign and magnitude of value as follows (d
represents a decimal digit):
┌──────────────────────────────────┬─────────┐
│ value range │ format │
├──────────────────────────────────┼─────────┤
│ > 999995000000000 │ inf? │
│999995000000000 - 999995000000 │ ddd.ddT │
│ 999995000000 - 999995000 │ ddd.ddG │
│ 999995000 - 999995 │ ddd.ddM │
│ 999995 - 999.995 │ ddd.ddK │
│ 999.995 - 0.005 │ ddd.dd │
│ 0.005 - -0.005 │ 0.00 │
│ -0.005 - -99.95 │ -dd.dd │
│ -99.995 - -99995 │ -dd.ddK │
│ -99995 - -99995000 │ -dd.ddM │
│ -99995000 - -99995000000 │ -dd.ddG │
│ -99995000000 - -99995000000000 │ -dd.ddT │
│ < -99995000000000 │ -inf? │
└──────────────────────────────────┴─────────┘
At the boundary points of the ranges, the chosen format will retain
the maximum number of significant digits.
pmNumberStr returns a pointer to a static buffer and hence is not
thread-safe. Multi-threaded applications should use pmNumberStr_r
instead.
printf(3)
This page is part of the PCP (Performance Co-Pilot) project.
Information about the project can be found at ⟨http://www.pcp.io/⟩.
If you have a bug report for this manual page, send it to
pcp@groups.io. This page was obtained from the project's upstream
Git repository ⟨https://github.com/performancecopilot/pcp.git⟩ on
2018-02-02. (At that time, the date of the most recent commit that
was found in the repository was 2018-02-02.) If you discover any
rendering problems in this HTML version of the page, or you believe
there is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
Performance Co-Pilot PCP PMNUMBERSTR(3)
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