MATLAB programming tips 2 - Input and Output Commands

MATLAB programming tips 2 - Input and Output Commands

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  11 Matlab Programming Tips Part2– Input / Output Commands (Review) by Shameer Koya
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  input Command  input- Prompt for user input.  Input is the simple basic command to request the user input.  Displays a prompt text for the user to understand what data to be entered and waits for the user to input a value and press the Return key.  i = input('Enter the current value:')  str = input(‘text’,'s') returns the entered text as a MATLAB string, without evaluating expressions. 2
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  sscanf Command  Readdata as string and convert to the other formats based on the definition.  X = sscanf(str, format, size)  Reads data from the vector str, converts it according to the format, and store the results in array X.  Argument ‘size’ is optional. 3
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  disp Command  disp- (display) command displays variable values or text on screen  Displays each time on new line.  Doesn't print variable name  disp(variable_name) or disp('text string') 4
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  fprintf Command  fprintf- Means file print formatted  'fprintf' is used to formats data and displays the results on the screen and to write the data in to a text file.  Can write to screen or to a file  Can mix numbers and text in output  Have full control of output display  Basic Syntax is  fprintf('Text to display') 5
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   >> fprintf('How are you' )  How are you>>  Problem – Command Window displays prompt (>>) at end of text, not at start of next line!  To make the prompt to appear on the start of a new line, n at the end of the fprintf text  >> fprintf( Electrical Engineeringn' )  Electrical Engineering  >>  Use n in middle of text to make MATLAB display remainder of text on next line  >> fprintf(' Electrical nEngineering')  Electrical  Engineering 6 fprintf …
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   To formatthe display data, the formatting operators are used.  A formatting operator starts with a percentage sign, %, and ends with a conversion character.  Common conversion specifiers:  %f fixed point (decimal always between 1's and 0.1's place, e.g., 3.14, 56.8  %e scientific notation, e.g, 2.99e+008  %d integers (no decimal point shown)  %s string of characters  >> fprintf( 'Joe is %d weighs %f kilos', age, weight )  >> fprintf( 'Joe weighs %f kilos', n1 ) 7 fprintf to format the output
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  fprintf to formatthe output …  Examples  >> age = 35;  >> weight = 75.25;  >> fprintf( 'Joe is %d weighs %f kilosn', age, weight )  Joe is 35 weighs 75.250000 kilos  >> fprintf( 'Joe weighs %4.4f kilosn', weight )  Joe weighs 75.2500 kilos  >> fprintf( 'Joe weighs %4.2f kilosn', weight )  Joe weighs 75.25 kilos 8
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  fprintf to formatthe output…  To display a percent sign, use %% in the text  To display a single quote, use ' ' in the text (two sequential single quotes)  To display a backslash, use in the text (two sequential backslashes) 9