decpoint.c File Reference

Functions for reading real numbers from strings which may contain either decimal dots or commas. More...

#include "libtpcmisc.h"

Go to the source code of this file.

Functions
int	dec_comma_is (char *str)
int	dec_separator (char *str)
void	dec_separator_change (char *str, int decsep)
double	atof_dpi (char *str)
int	dec_nr (char *str)
int	atof_with_check (char *double_as_string, double *result_value)
char *	strPtrToNextValue (char *str, char **nxtp)
int	atoi_with_check (const char *int_as_string, int *result_value)

Detailed Description

Functions for reading real numbers from strings which may contain either decimal dots or commas.

Author

Vesa Oikonen

Definition in file decpoint.c.

Function Documentation

atof_dpi()

double atof_dpi

(

char *

str

)

Replacement of atof(), which works whether string contains decimal dots or decimal commas. Possible commas are replaced by dots in the argument string.

Returns

Returns the double float.

Parameters

str	Pointer to string (not modified).

Definition at line 59 of file decpoint.c.

  {
  char *cptr;
  double f;
 
  if(str==NULL) return(nan(""));
  /* If string contains a dot, then use atof directly */
  if(strchr(str, '.')!=NULL) return(atof(str));
  /* Otherwise, convert all commas to dots */
  //while((cptr=strchr(str, ','))!=NULL) *cptr='.';
  cptr=strchr(str, ','); if(cptr!=NULL) *cptr='.';
  f=atof(str); if(cptr!=NULL) *cptr=',';
  return(f);
}

Referenced by atof_with_check(), csv2dft_a(), csv2dft_b(), dft_fill_hdr_from_IFT(), dftRead(), fitRead(), and resRead().

atof_with_check()

int atof_with_check	(	char *	double_as_string,
		double *	result_value )

Converts a string to float using atof(), but if its return value is zero this function checks that argument string actually contains a number. Result value is set to NaN if string was not valid value. Both decimal point and comma are accepted.

Returns

Returns 0 if successful, and 1 in case of an error.

Parameters

double_as_string	String which is converted to a double; not modified
result_value	Pointer to the double float; enter NULL, if not needed

Definition at line 107 of file decpoint.c.

  {
  char* cptr;
  double f;
 
  if(result_value!=NULL) *result_value=nan("");
  if(double_as_string==NULL) return(1);
  f=atof_dpi(double_as_string);
  if(f!=0.0) {if(result_value!=NULL) *result_value=f; return(0);}
  cptr=double_as_string;
  while(*cptr!=0 && (*cptr=='+' || *cptr=='-' || *cptr==' ')) cptr++;
  if(*cptr=='0') {if(result_value!=NULL) *result_value=f; return(0);}
  return(1);
}

Referenced by csv2dft_linkset(), csv2dft_mat(), dftRead(), and readEcat931Calibrationfile().

atoi_with_check()

int atoi_with_check	(	const char *	int_as_string,
		int *	result_value )

Converts a string to integer (int) using atoi, but this function verifies that argument string actually contains an integer number. String must end in NULL character. Exponentials are not accepted. Result value is set to 0 if string was not valid value.

Returns

Returns 0 if successful, and 1 in case of an error.

Parameters

int_as_string	String which is converted to a int; not modified
result_value	Pointer to the int; enter NULL, if not needed

Definition at line 238 of file decpoint.c.

  {
  int i, len;
 
  if(result_value!=NULL) *result_value=0;
  if(int_as_string==NULL) return(1);
  len=strlen(int_as_string); if(len<1) return(1);
  /* First character can be + or - */
  i=strspn(int_as_string, "+-");
  if(i>1) return(1);
  if(i==1 && len==1) return(1); 
  /* Check that (rest of) characters are digits */
  for( ; i<len; i++) if(!isdigit(int_as_string[i])) return(1);
  /* Convert to int */
  if(result_value!=NULL) *result_value=atoi(int_as_string);
  return(0);
}

Referenced by integerListAddFromString(), and pxlRead().

dec_comma_is()

int dec_comma_is

(

char *

str

)

Checks whether argument string contains a decimal comma instead of dot.

Returns

Returns 1 if decimal comma is found and 0 if not found.

Parameters

str	Pointer to string (not modified).

Definition at line 14 of file decpoint.c.

  {
  if(strchr(str, '.')!=NULL) return(0);
  if(strchr(str, ',')!=NULL) return(1);
  return(0);
}

dec_nr()

int dec_nr

(

char *

str

)

Returns the number of decimal places in the argument string, representing a floating point value. String can contain either decimal dots or commas.

Definition at line 81 of file decpoint.c.

{
  char *cptr;
  int n;
 
  if(str==NULL) return 0;
  /* Find the first dot or comma, but stop with E */
  cptr=str;
  while(*cptr!='.' && *cptr!=',') {
    if(*cptr==(char)0 || *cptr=='E' || *cptr=='e') return 0;
    cptr++;
  }
  if(*cptr==(char)0 || (*cptr!='.' && *cptr!=',')) return 0;
  /* Calculate the number of digits that follows */
  cptr++; n=0; while(cptr!=NULL && isdigit(*cptr)) {n++; cptr++;}
  return n;
}

Referenced by dftRead().

dec_separator()

int dec_separator

(

char *

str

)

Checks whether argument string contains a decimal comma or dot, or neither.

Returns

Returns 0, if neither is found, 1 if dot, and 2 if comma is found.

Parameters

str	Pointer to string (not modified).

Definition at line 28 of file decpoint.c.

  {
  if(strchr(str, '.')!=NULL) return(1);
  if(strchr(str, ',')!=NULL) return(2);
  return(0);
}

dec_separator_change()

void dec_separator_change	(	char *	str,
		int	decsep )

Convert the first decimal separator to comma or dot, as required.

Parameters

str	Pointer to string (modified when necessary).
decsep	Requested decimal separator: 0=dot, 1=comma.

Definition at line 40 of file decpoint.c.

  {
  char *cptr;
  cptr=strchr(str, '.'); if(cptr!=NULL && decsep==1) {*cptr=','; return;}
  cptr=strchr(str, ','); if(cptr!=NULL && decsep==0) {*cptr='.'; return;}
  return;
}

strPtrToNextValue()

char * strPtrToNextValue	(	char *	str,
		char **	nxtp )

This function searches the given string for a string representation of numerical value, possibly with decimal and exponent part. Returns also pointer to the string right after where the numerical value ended, and from where the next number can be searched. Return Returns pointer to start of the next string, or NULL if not found.

Parameters

str	Pointer to string where numerical values are searched; not changed.
nxtp	Obligatory pointer to string pointer, which will be set to point to the first character after value string, or to NULL if string ends.

Definition at line 134 of file decpoint.c.

  {
  char *cptr, *strt;
  unsigned int i, j, n=0;
 
  // search the start
  if(str==NULL || strlen(str)<1) {*nxtp=NULL; return NULL;}
  // find the index where number might start
  cptr=str;
  do {
    i=strcspn(cptr, "+-0123456789"); if(i==strlen(cptr)) {*nxtp=NULL; return NULL;}
    strt=cptr+i;
    // any previous character must be a separator
    if(i>0) {cptr=strt-1; i=strcspn(cptr, " \t,;"); if(i>0) cptr+=i;}
  } while(i>0);
  // get past + and - ; if more than one, that is an error
  cptr=strt; if(*cptr=='-' || *cptr=='+') {n++; cptr++;}
  // get past first set of numbers
  i=strspn(cptr, "0123456789"); n+=i;
  if(i<1) {*nxtp=cptr; return NULL;}
  cptr+=i; n+=i;
  // get past decimal separator
  i=strspn(cptr, ",.");
  if(i==0) { // there was none, thus we're done
    *nxtp=cptr; return strt; 
  } else if(i>1) { // can't be more than one decimal separator
    *nxtp=cptr; return strt;
  }
  cptr+=1; n+=1;
  // after decimal separator we must have numbers again
  i=strspn(cptr, "0123456789");
  if(i<1) { // what was thought to be decimal separator was not that
    *nxtp=cptr-1; return strt;
  }
  cptr+=i; n+=i;
  // check if we have exponent part
  if(*cptr=='E' || *cptr=='e') i=1; else i=0;
  // if not, then we're done
  if(i==0) {*nxtp=cptr; return strt;}
  cptr+=1;
  // we may have signed exponent
  if(*cptr=='-' || *cptr=='+') {cptr+=1; i++;}
  // after exponent we must have numbers again
  j=strspn(cptr, "0123456789");
  if(j<1) { // what was thought to be exponent was not that
    *nxtp=cptr-i; return strt;
  }
  cptr+=j; n+=j;
  // now this must be the end
  *nxtp=cptr;
  return strt;
}