Kill a warning

[drf5n]

I got this warning:

% make magneto
cc     magneto.c   -o magneto
magneto.c:58:13: warning: format specifies type 'char *' but the argument has type 'char (*)[64]' [-Wformat]
 scanf("%s",&filename);
        ~~  ^~~~~~~~~
1 warning generated.

Since filename is already a char * buffer, it doesn't need to be a reference to a specific array type.

I also needed to change #include <malloc.h> to #include <stdlib.h> to compile on my Mac, but I didn't put that in the PR.

diff --git a/magneto/magneto.c b/magneto/magneto.c
index e1b6d62..e7bf01c 100644
--- a/magneto/magneto.c
+++ b/magneto/magneto.c
@@ -5,7 +5,8 @@
 
 #include <stdio.h>
 #include <math.h>
-#include <malloc.h>
+//#include <malloc.h>
+#include <stdlib.h>
 #include <string.h>
 #include <float.h>
 
@@ -54,7 +55,7 @@ int main()
   FILE *fp;
 
  printf("\r\nMagneto 1.2\r\n.csv input file name? ");
- scanf("%s",&filename);
+ scanf("%s",filename);
 
  fp = fopen(filename, "r");
  if (fp == NULL) {printf("file not found"); return 0;}

[drf5n]

Downloading the MagCal data from https://github.com/hightower70/MagCal/blob/master/mag.txt and translating it into mag.csv with

awk '{print $1","$2","$3}' mag.txt > mag.csv

gives this truncated result:

Magneto 1.2
.csv input file name? mag.csv
0      0.0     -0.3     -0.4
1     -0.0     -0.2     -0.5
2     -0.0     -0.2     -0.6
3     -0.0     -0.2     -0.5
4     -0.0     -0.2     -0.5
5     -0.0     -0.2     -0.5
...
25596      0.4      0.2     -0.4
25597      0.4      0.2     -0.4
25598      0.4      0.2     -0.4

Average length of 25599 input vectors = 0.581882

Expected norm of local field vector? 1

Combined bias vector B:
   -0.02     0.01    -0.03 

Correction matrix Ainv, using Hm=1.000000:
  1.68185  -0.03130   0.01154
 -0.03130   1.69514   0.00581
  0.01154   0.00581   1.82099

Where Hcalc = Ainv*(H-B)

Code initialization statements...

 float B {   -0.02,    0.01,   -0.03};

 float Ainv {{  1.68185, -0.03130,  0.01154},
             { -0.03130,  1.69514,  0.00581},
             {  0.01154,  0.00581,  1.82099}};