How to read a float in a csv with CAPL?

2019-07-17 08:57发布

问题:

I have a .csv file and I want to read the data in its format, not at string. This is the function that save the file in a readbuffer if is ok.

fileGetString(readbuffer,elcount(readbuffer),readHandle)!=0)

And I have the data is in this format:

Temperature;12.25;15.65;-25.12;80;
Time;1;2;4;7;

I want save the temperature in a buffer "Temperature[i]" and do the same with the time "Time[i]" How can I do this in CAPL?

I know that I can read each data like String and cast to integer or float doing some operations, but I want optimize code and read each data in its format.

回答1:

You can convert an string to an float number using strtod(). Just for fun, here is complete example:

on start
{
  dword fh;
  char text[255];  
  double Temperature[4], Time[4];
  int i;

  /* open file */
  fh = openFileRead("a.csv",0);
  if (!fh) {
    write ("ERROR: Open file failed!");
    return;
  }

  /* read the 'Temperature' line */
  if (!fileGetString(text, elcount(text), fh) ||
      strstr(text, "Temperature;") != 0) {
    write("ERROR: Wrong file format, 'Temperature' not found!");
    return;
  }

  /* get the 'Temperature' values */
  getValuesFromCsvString(text, Temperature);

  /* read the 'Time' line */
  if (!fileGetString(text, elcount(text), fh) ||
      strstr(text, "Time;") != 0) {
    write("ERROR: Wrong file format, 'Time' not found!");
    return;
  }

  /* get the 'Time' values */
  getValuesFromCsvString(text, Time);

  /* output values */
  for (i = 0; i < elcount(Temperature); i++)
    write("Temperature[%i] = %6.2f", i, Temperature[i]);  
  for (i = 0; i < elcount(Time); i++)
    write("Time[%i] = %2.0f", i, Time[i]);    
}

int getValuesFromCsvString(char text[], double vals[])
{
  long i, pos;
  double res;

  pos = strstr(text, ";");
  str_replace(text, ";", " ");

  for (i = 0; i < elcount(vals) ; i++) {
    pos = strtod(text, pos, res);
    if (pos >= 0)
      vals[i] = res;
    else
      break;
  }

  return 0;
}

Output:

Temperature[0] =  12.25
Temperature[1] =  15.65
Temperature[2] = -25.12
Temperature[3] =  80.00
Time[0] =  1
Time[1] =  2
Time[2] =  4
Time[3] =  7


标签: csv capl