section m of routines in std.i

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functions in std.i - m

mac_primitives


    mac_primitives, file  


sets FILE primitive data types to be native to MacIntosh, 8 byte double.  
Interpreted function, defined at i0/std.i   line 2913

macl_primitives


    macl_primitives, file  


sets FILE primitive data types to be native to MacIntosh, long double.  
Interpreted function, defined at i0/std.i   line 2921

max


    max(x)  
 or max(x, y, z, ...)  


returns the scalar maximum value of its array argument, or, if  
more than one argument is supplied, returns an array of the  
maximum value for each array element among the several arguments.  
In the multi-argument case, the arguments must be conformable.  
Builtin function, documented at i0/std.i   line 811

SEE ALSO: min, sum, avg

median


    median(x)  
 or median(x, which)  


returns the median of the array X.  The search for the median takes  
place along the dimension of X specified by WHICH.  WHICH defaults  
to 1, meaning the first index of X.  The median function returns an  
array with one fewer dimension than its argument X (the WHICH  
dimension of X is missing in the result), in exact analogy with  
rank reducing index range functions.  If dimsof(X)(WHICH) is  
odd, the result will have the same data type as X; if even, the  
result will be a float or a double, since the median is defined  
as the arithmetic mean between the two central values in that  
case.  
Interpreted function, defined at i0/std.i   line 1231

SEE ALSO: sort

merge


    merge(true_expr, false_expr, condition)  


returns the values TRUE_EXPR or FALSE_EXPR where CONDITION is  
non-zero or zero, respectively.  The result has the data type of  
TRUE_EXPR or FALSE_EXPR, promoted to the higher arithmetic type  
if necessary.  The result has the dimensions of CONDITION.  
The number of elements in TRUE_EXPR must match the number of  
non-zero elements of CONDITION, and the number of elements in  
FALSE_EXPR must match the number of zero elements of CONDITION.  
(TRUE_EXPR or FALSE_EXPR should be nil if there are no such  
elements of CONDITION.  Normally, TRUE_EXPR and FALSE_EXPR should  
be 1-D arrays if they are not nil.)  
This function is intended for vectorizing a function whose  
domain is divided into two or more parts, as in:  
   func f(x) {  
     big= (x>=threshhold);  
     wb= where(big);  
     ws= where(!big);  
     if (is_array(wb)) {  
       xx= x(wb);  
       fb=   
     }  
     if (is_array(ws)) {  
       xx= x(ws);  
       fs=   
     }  
     return merge(fb, fs, big);  
   }  
Builtin function, documented at i0/std.i   line 894

SEE ALSO: mergef, merge2, where

merge2


    merge2(true_expr, false_expr, condition)  


returns the values TRUE_EXPR or FALSE_EXPR where CONDITION is  
non-zero or zero, respectively.  The result has the data type of  
TRUE_EXPR or FALSE_EXPR, promoted to the higher arithmetic type  
if necessary.  Unlike the merge function, TRUE_EXPR and FALSE_EXPR  
must be conformable with each other, and with the CONDITION.  
Interpreted function, defined at i0/std.i   line 925

SEE ALSO: merge, where, mergef

mergef


    y = mergef(x, f1, cond1, f2, cond2, ... felse)  


  Evaluate F1(X(where(COND1))), F2(X(where(COND2))),  
  and so on, until FELSE(X(where(!(COND1 | COND2 | ...))))  
  and merge all the results back into an array Y with the  
  same dimensions as X.  Each of the CONDi must have the  
  same dimensions as X, and they must be mutally exclusive.  
  
  During the evaluation of Fi, note that all of the local  
  variables of the caller of mergef are available.  The  
  Fi are invoked as Fi(X(mergel)) and  the variable mergel  
  = where(CONDi) is available to the Fi, in case they need  
  to extract any additional parameters.  If noneof(CONDi)  
  then Fi will not be called at all, otherwise, the Fi are  
  invoked in order.  The return value of Fi must have the same  
  shape as its argument (which will be a 1D array or scalar).  
  
  Use mergeg to construct secondary results the same shape  
  as X and Y.  
  
   Interpreted function, defined at i0/std.i   line 947

SEE ALSO: mergeg, merge

mergeg


    z = mergeg(z, value)  
 or z = mergeg(z)  


  If secondary results are to be returned from a mergef, besides  
  its return value, the Fi may construct them using the second  
  form of mergef:  
    z = mergeg(z, value)  
  where z is a variable in the original caller of mergef,  
  and value is its value where(CONDi).  Note that the variable  
  name of the first parameter must be the same as the variable  
  name it is assigned to in this construction -- that variable  
  is being used to hold the state of z as it is built.  After  
  the outer mergef returns, the caller needs to invoke  
    z = mergeg(z)  
  one final time to complete each secondary return value.  
  
  z = [];  
  y = mergef(x, f1, cond, f2);  
  z = mergeg(z);  
  ...  
  func f1(x) {   
    z = mergeg(z, exprz(x));  
    return expry(x);  
  }  
  func f2(x) {   
    z = mergeg(z, exprz(x));  
    return expry(x);  
  }  
  
   Interpreted function, defined at i0/std.i   line 993

SEE ALSO: mergef, merge

min


    min(x)  
 or min(x, y, z, ...)  


returns the scalar minimum value of its array argument, or, if  
more than one argument is supplied, returns an array of the  
minimum value for each array element among the several arguments.  
In the multi-argument case, the arguments must be conformable.  
Builtin function, documented at i0/std.i   line 801

SEE ALSO: max, sum, avg

mkdir


    mkdir, directory_name  
    rmdir, directory_name  


Create DIRECTORY_NAME with mkdir, or remove it with rmdir.  
The rmdir function only works if the directory is empty.  
Builtin function, documented at i0/std.i   line 2478

SEE ALSO: cd, lsdir, get_cwd, get_home