If z is a scalar, result is a scalar double precision apparent magnitude. If z is an array, result is a double precision array with the apparent magnitude for each z value.
The function magmax returns -1000 in case of insufficient memory, file i/o problems and numerical problems with the given cosmology. An error message describing the problem is printed in the IDL window. The function returns -2000 if the specified filter does not match the spectrum at this redshift. This is also shown by printing an error message to the IDL window.
The different errors catched by the program are:
| Error message | Description |
| Error while opening file for reading spectrum: <path> | This means that the file described by <path> does not exist there or can't be opened for some other reason. |
| Error while reading spectrum: Out of memory! <path> | There was not enough free memory available to store the spectrum. |
| Error while reading spectrum: Wrong file structure! <path> | This means that the data in the file described by <path> is not written in the right way, that is, does not contain two floating point numbers per line, separated by white space characters. |
| Error while opening file for reading filter: <path> | This means that the file described by <path> does not exist there or can't be opened for some other reason. |
| Error while reading filter: Out of memory! <path> | There was not enough free memory available to store the filter. |
| Error while reading filter: Wrong file structure! <path> | This means that the data in the file described by <path> is not written in the right way, that is, does not contain two floating point numbers per line, separated by white space characters. |
| Out of memory | There was not enough memory available to make a copy of the spectrum in function magnitude. |
| Error in integration: Out of memory while interpolating filter data! | In function interpolate there was not enough free memory available to store the interpolated data of the filter. |
| Error in integration: Filter does not match spectrum at this redshift! | Either the starting point of the filter is at a smaller wavelength than the starting point of the redshifted spectrum or the end point of the filter is at a higher wavelength than the end point of the redshifted spectrum. |
| Error in integration: Out of memory! | There was not enough free memory available in function integrate. |
| Error in integration: Out of memory while interpolating spectrum data! | In function interpolate there was not enough free memory available to store the interpolated data of the filter. |