Perl科学计算(1.2)
Perl科学计算(1.2)1 #分布函数
2 my @ex8=(1,9,4,9,10,12,13,15,12,13);
3 my %hash=&frequency(\@ex8);
4 print join(",",values %hash);
5 print join(",",keys %hash);
6
7 sub frequency{
8 my($vec)=@_;
9 my %hash;
10 foreach(@$vec){
11 ++$hash{$_};
12 }
13 return %hash;
14 }
15
16 #排序函数
17 my @ex9=(1,9,4,9,10,12,13,15,12,13);
18 printjoin(',',&sortf("numeric","asc",\@ex9));
19
20 sub sortf{
21 my($type,$direction,$vec)=@_;
22 my @vec_sort;
23 if(($type eq "numeric") & ($direction eq "asc")){
24 @vec_sort=sort{$a<=>$b}@$vec;
25 }
26 if(($type eq "numeric") & ($direction eq "desc")){
27 @vec_sort=sort{$b<=>$a}@$vec;
28 }
29 if(($type eq "string") & ($direction eq "asc")){
30 @vec_sort=sort{$a cmp $b}@$vec;
31 }
32 if(($type eq "string") & ($direction eq "desc")){
33 @vec_sort=sort{$b cmp $a}@$vec;
34 }
35 return @vec_sort;
36 }
37
38 #众数
39 my @ex10=(1,9,4,9,10,12,13,15,12,13);
40 print join(',',&mode(\@ex10));
41
42 sub mode{
43 my($vec)=@_;
44 my %hash=&frequency($vec);
45 my @result;
46 foreach(sort{ $hash{$b}<=>$hash{$a} }keys %hash){
47 last if @result && $hash{$_} != $hash{$result};
48 push(@result,$_);
49 }
50 return @result;
51 }
52
53 #中位数
54 my @ex111=(1,9,4,5);
55 print &median(\@ex11);
56 my @ex112=(1,9,4,5,5);
57
58 sub median{
59 my($vec)=@_;
60 my @vec1=&sortf('numeric','asc',$vec);
61 my $length=scalar @$vec;
62 my $result;
63 if($length % 2){
64 $result=$vec1[($length-1)/2];
65 }else{
66 $result=($vec1[$length/2]+$vec1[$length/2-1])/2;
67 }
68 return $result;
69 }
70
71 #四分之一分位数
72
73my @ex12=( 7, 15, 36, 39, 40, 41);
74 print join(',',&quantile(\@ex12));
75
76 sub quantile{
77 my($vec)=@_;
78 my @vec1=&sortf('numeric','asc',$vec);
79 my $length=scalar @$vec+1;
80 my($upper,$lower);
81 if($length %4 ){
82 my $temp1=int($length/4);
83 my $temp2=int(3*$length/4);
84 $upper=$vec1[$temp1-1]+($vec1[$temp1]-$vec1[$temp1-1])*($length/4-$temp1);
85 $lower=$vec1[$temp2-1]+($vec1[$temp2]-$vec1[$temp2-1])*(3*$length/4-$temp2);
86 }else{
87 $upper=$vec1[$length/4-1];
88 $lower=$vec1;
89 }
90 my @result=($upper,$lower);
91 return @result;
92 }
93
94 #最大值
95 my @ex13=( 7, 15, 36, 39, 40, 41);
96 print &max(\@ex13);
97
98 sub max{
99 my($vec)=@_;
100 my @result=&sortf('numeric','desc',$vec);
101 return $result;
102 }
103
104 #最小值
105 my @ex14=( 7, 15, 36, 39, 40, 41);
106 print &min(\@ex14);
107
108 sub min{
109 my($vec)=@_;
110 my @result=&sortf('numeric','asc',$vec);
111 return $result;
112 };
113 #标准化，共2种方法
114 my @ex15=( 7, 15, 36, 39, 40, 41);
115 print join(',',&scale(\@ex15,2));
116
117 sub scale{
118 my($vec,$m)=@_;
119 my @result;
120 if($m eq 1){
121 if(&max($vec) eq &min($vec)){
122 die "could not scale as range method!";
123 }else{
124 @result=map(($_-&min($vec))/(&max($vec)-&min($vec)),@$vec);
125 }
126 return @result;
127 }
128 if($m eq2){
129 if(&var($vec) eq 0){
130 die "could not scale as centered method!";
131 }else{
132 @result=map(($_-&mean($vec))/&sd($vec),@$vec);
133 }
134 return @result;
135 }
136 }
137
页:
[1]