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gibson:teaching:fall-2014:math445:lecture7-diary [2014/10/07 11:35]
gibson [A few more bells and whistles]
gibson:teaching:fall-2014:math445:lecture7-diary [2014/10/07 11:44]
gibson [A function with an if statement and fprintf]
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   -The //body// of the function lies between the help string and the ''​end''​. Here the function body is a single line of code that calculates ''​tempC''​ from ''​tempF''​.   -The //body// of the function lies between the help string and the ''​end''​. Here the function body is a single line of code that calculates ''​tempC''​ from ''​tempF''​.
  
-====A few more bells and whistles====+====A function with an if statement ​and fprintf====
  
 That was an exceedingly simple function. Let's write the inverse function ''​celsius2faren''​ with a few more bells and whistles. Specifically,​ let's print a warning message if the input temperature is below absolute zero, -273.15 C.  That was an exceedingly simple function. Let's write the inverse function ''​celsius2faren''​ with a few more bells and whistles. Specifically,​ let's print a warning message if the input temperature is below absolute zero, -273.15 C. 
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 </​code>​ </​code>​
  
-Things ​to note here+This code includes an ''​if''​ statement that checks for temperatures below absolute zero. If the condition of the ''​if''​ statement evaluates ​to true, then the body of the ''​if''​ statement will be executed. If it evaluates to false, the body will be skipped, and execution will resume immediately after the ''​end''​. Thus here the warning message will be printed only if ''​tempC''​ is less than -273.15.  
 + 
 + 
 +The warning message is printed using the //formatted print function// ''​fprintf''​. ''​fprintf''​ takes a variable number of arguments. The first argument is always the ''​format string''​. The format string is simply a message to be printed with a number of slots into which values of variables will be substituted. The slots are marked with percent signs ''​%'',​ and following the percents signs is a letter code that tells Matlab what type of variable to expect for the slot. Here ''​%d''​ tells Matlab to expect a decimal-valued variable (i.e. a floating-point number). After the format string, the remaining arguments to ''​fprintf''​ are the variables whose values you want substituted into those slots.  
gibson/teaching/fall-2014/math445/lecture7-diary.txt · Last modified: 2014/10/07 11:44 by gibson