apop_asst.c File Reference

Functions

• double apop_generalized_harmonic (int N, double s)
• char * apop_strip_dots (char *in, char strip_type)
• void apop_error (int level, char stop, char *msg,...)
• int apop_system (const char *fmt,...)
• apop_data * apop_data_sort (apop_data *data, int sortby, char asc)
• double * apop_vector_percentiles (gsl_vector *data, char rounding)

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Detailed Description

The odds and ends bin. Copyright (c) 2005--2007 by Ben Klemens. Licensed under the modified GNU GPL v2; see COPYING and COPYING2.

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Function Documentation

apop_data* apop_data_sort	(	apop_data *	data,
		int	sortby,
		char	asc
	)

This function sorts the whole of a apop_data set based on one column. Sorts in place, with little additional memory used.

Uses the gsl_sort_vector_index function internally, and that function just ignores NaNs; therefore this function just leaves NaNs exactly where they lay.

Parameters:

	data	The input set to be modified. (No default, must not be NULL.)
	sortby	The column of data by which the sorting will take place. As usual, -1 indicates the vector element. (default: column zero of the matrix)
	asc	If 'd' or 'D', sort in descending order; else sort in ascending order. (Default: ascending)

Returns:

A pointer to the data set, so you can do things like apop_data_show(apop_data_sort(d, -1)).

This function uses the Designated initializers syntax for inputs.

void apop_error	(	int	level,
		char	stop,
		char *	msg,
			...
	)

Inform the user of a faux pas. See also Apop_assert, which allows the function to return a value.

Parameters:

	level	At what verbosity level should the user be warned? E.g., if level==2, then print iff apop_opts.verbosity >= 2. You can set apop_opts.verbose==-1 to turn off virtually all messages, but this is probably ill-advised.
	stop	Either 's' or 'c', indicating whether the program should stop or continue. If stopping, uses assert(0) for easy debugging. You can use 'h' (halt) as a synonym for 's'.
	msg	The message to write to STDERR (presuming the verbosity level is high enough). This can be a printf-style format with following arguments. You can produce much more informative error messages this way, e.g., apop_error(0, 's', "Beta is %g but should be greater than zero.", beta);.

double apop_generalized_harmonic	(	int	N,
		double	s
	)

Calculate

int apop_system	(	const char *	fmt,
			...
	)

Call system(), but with printf-style arguments. E.g.,

char filenames[] = "apop_asst.c apop_asst.o"
apop_system("ls -l %s", filenames);

Returns:

The return value of the system() call.

double* apop_vector_percentiles	(	gsl_vector *	data,
		char	rounding
	)

Returns a vector of size 101, where returned_vector[95] gives the value of the 95th percentile, for example. Returned_vector[100] is always the maximum value, and returned_vector[0] is always the min (regardless of rounding rule).

Parameters:

	data	a gsl_vector of data. (No default, must not be NULL.)
	rounding	This will either be 'u', 'd', or 'a'. Unless your data is exactly a multiple of 101, some percentiles will be ambiguous. If 'u', then round up (use the next highest value); if 'd' (or anything else), round down to the next lowest value; if 'a', take the mean of the two nearest points. If 'u' or 'a', then you can say "5% or more of the sample is below returned_vector[5]"; if 'd' or 'a', then you can say "5% or more of the sample is above returned_vector[5]". (Default = 'd'.)

This function uses the Designated initializers syntax for inputs.