IDL STRMID HOW TO

IDL STRMID HOW TO

And I want the plus sign for DEC1 part, too.В So letвЂ™s look at how to add 0s first!ДЇor integer formatting it is easy.В I replace I3В with I03. So I need 0В rather than backspace before 8В and 5.95. Quite bad, right? So having prepending backspaceВ is good thing.В But for printing purpose, in publication or in thesis, it is better if they were shown like this: 19 50 46.99 +08 52 05.95 Without this hassle for backspace, the output would have looked like: 195046.99 8525.95 And if the integer is of less than 3 digits, then non-existing integer part is replaced by backspace.В I used this fact to make some space between two entries, like DEC1 and DEC2. It prints 3 digit integer, aligned to right. Which is perfectly fine for quick look-up.В As you see, the formatВ defines how the output should look like. When I want to print it with following command:

Of course, I save last part of RA and DEC in floating number, whereas other variable are of integer. So I save these information in IDL in variable such as, RA1, RA2, RA3, DEC1, DEC2, DEC3. Only declination needs plus or minus sign, like latitude on EarthвЂ™s surface. For example, for Altair, one of the brightest star in the sky, it has RA of and DEC of. This allows simple extraction of strings from the end.The coordinates of any objects in astronomy is given in right ascension and declination, sort of latitude and longitude for the sky. Length then proceeds from this position to the right, toward the end of the string. Specifies that First_Character should be counted from the end of the string rather than the beginning. If Length is not supplied, STRMID extracts all characters from the specified start position to the end of the string. If there are not enough characters left in the main string to obtain Length characters, the substring is truncated. The starting position within Expression at which the substring starts. If this argument is not a string, it is converted using IDL's default formatting rules. The expression from which the substrings are to be extracted. If it is greater than 1, the result will have an additional dimension, with the new first dimension having the same size as the stride. If the stride is 1, the result will have the same structure and number of elements as Expression.If First_Character or Length do not contain enough elements to process Expression, STRMID automatically loops back to the beginning as necessary.If both are arrays, they must have the same stride.If First_Character or Length is an array, the size of their first dimension determines how many substrings are extracted from each element of Expression.The result has the same structure and number of elements as Expression. If a scalar value is supplied for First_Character and Length, then those values are applied to all elements of Expression.Either argument can be a scalar or an array: The form of First_Character and Length control how they are applied to Expression. The result of the function is a string of Length characters taken from Expression, starting at character position First_Character. Result = STRMID( Expression, First_Character ,В /REVERSE_OFFSET ) Return Value The string we want to remove is highlighted in yellow: myQuote = 'It is not in the stars to hold our destiny but in ourselves.' extractedStr = STRMID(myQuote, 29, 12, /REVERSE_OFFSET) PRINT, extractedStr Remember that the first character in the original string is at position zero (0): myString = 'IDL is fun' subString = STRMID(myString, 4, 2) PRINT, subStringД®xtract a substring from the end of a string (quote fromВ William Shakespeare). ExamplesД®xtract a substring, in this case: вЂњisвЂќ, from a longer string and store it in another variable.

Each extracted string is the result of removing characters from the input string. The STRMID function extracts one or more substrings from a string expression. Tip: See also the IDL_String::CharAt, IDL_String::Remove, and IDL_String::Substring methods, which provide similar functionality but with an object-oriented interface.

Idl strmid