perl - 将字符串转换为数字 “Argument isn’ t 数字错误”

Question

我正在解析制表符分隔的文件。有几列没有被识别为数字，即使它们显然是数字。当我尝试总结这些值时，会显示错误:Argument ""97""isn't numeric in addition (+) 并且 Perl 返回 0。

我试过使用 Scalar::Util qw(looks_like_number); 但它产生了相同的结果“0”。还有什么我可以尝试的吗？

代码如下:

open my $out_fh, '>', $final_variants or die qq{Unable to open "$final_variants" for output: $!};

open my $in_fh, '<', $tsv_file_new
            or die qq{Unable to open "$tsv_file_new" for input: $!};

while ( <$in_fh> ) {

        my @fields = split;

        my $forward_reference = $fields[67];
        my $reverse_reference = $fields[68];
        my $forward_variant_reads = $fields[77];
        my $reverse_variant_reads = $fields[78];

        my $total_reads = (looks_like_number($forward_reference))
                + (looks_like_number($reverse_reference))
                + (looks_like_number($forward_variant_reads))
                + (looks_like_number($reverse_variant_reads));

        my $current_final_line = $headerline . "\t"
                    . $forward_reference . "\t"
                    . $reverse_reference . "\t"
                    . $forward_variant_reads . "\t"
                    . $reverse_variant_reads . "\t"
                    . $total_reads . "\t";

        print $out_fh $current_final_line, "\n";
}

Answer 1

您的错误消息已经说明了这一点:参数“97”不是数字。当 number 实际上是一个被引号 (") 包围的字符串 时，就会发生这种情况， 如下所示:

my $num = '"42"';
my $sum = $num + 1;

这给出:

Argument ""42"" isn't numeric in addition (+) at...

尝试去掉您的数字中的引号:

$num =~ s/"//g;