如何使用“diff”或其他命令獲得差異比率？

我有兩個包含數千行的文件。我想使用diff、vimdiff或其他命令獲得它們在行/字節中的差異比率，即使無論具體差異如何。

有一個名為diffstat聽起來像您正在尋找的工具。

$ diff <file1> <file2> | diffstat

例子

$ diff afpuri.c afpuri1.c | diffstat
unknown |   53 ++++++++++++++++++++---------------------------------
1 file changed, 20 insertions(+), 33 deletions(-)

這也可用於diff在樹中包含多個文件的輸出。

參考

• 如何獲取差異以報告新行、已更改行和已刪除行的摘要

我的數學可能有點偏離，但我相信你要求一個比率，我相信這會產生一個比率。

#!/usr/bin/env bash

# File 1 contains 1,2,3,4,5 on new lines
# File 2 contains 1,2,3,4,5,6,7,8,9,10 on new lines.

# Compare differentials side-by-side
diff -y 1 2 > diff

# Print lines to file which do not contain ">" prefix.
sed 's/[ ]/d' diff > MATCHES

# Print lines to file which do contain ">" prefix.
sed '/[>]/!d' diff > DIFFS

# Count lines in file that contains MATCHES between Versions of Files 1,2.
MATCHES=$(wc -l MATCHES | sed 's/[^0-9]*//g')

# Count lines in file that DID NOT MATCH between Version of Files 1,2.
DIFFS=$(wc -l DIFFS | sed 's/[^0-9]*//g')

# Sed here is stripping all but the number of lines in file.

RATIO=$(echo "$MATCHES / $DIFFS" | bc -l)

# To get the ratio, we are echoing the #of_matches and the #of_diffs to
# the bc -l command which will give us a float, if we need it.
echo "You've got:" $RATIO "differential."

# Bytes...
# stat -c%s prints bytes to variable
MATCHES=$(stat -c%s MATCHES)
DIFFS=$(stat -c%s DIFFS)

RATIO_BYTE=$(echo "$MATCHES / $DIFFS" | bc -l)
echo "Let Ratio in Bytes be" $RATIO_BYTE
# Again, we divide the matches by the diffs to reach the "ratio" of
# differences between the files.

引用自：https://unix.stackexchange.com/questions/159517