See functions (see, see_col, head_col, tail_col)

func_see.sh

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+
+# SEE & SEE_COL
+#-------------------------------------------------------------------------------
+# What: See file contents quickly, i.e., head and tail
+# Who: Gregor Gorjanc
+# When:
+#  * 2013-12 Initial version
+#-------------------------------------------------------------------------------
+
+see()
+{
+  ## $@ = file names
+  lines=5
+  col_limit=20
+  for f in "$@"; do
+    nc=$(head -n 1 $f | awk '{ print NF }')
+    if [ $nc -gt $col_limit ]; then
+      echo -e "\nMore than ${col_limit} columns, using see_col!"
+      see_col $f
+    else
+      nr=$(wc -l $f | awk '{ print $1 }')
+      echo "\n$f, nrow=$nr, ncol=$nc"
+      head -n $lines $f
+      if [ $nr -gt $lines ]; then
+        echo "..."
+        echo "..."
+        echo "..."
+        tail -n $lines $f
+      fi
+    fi
+  done
+}
+export -f see
+
+see_col()
+{
+  ## $@ = file names
+  lines=5
+  for f in $@; do
+    nc=$(head -n 1 $f | awk '{ print NF }')
+    nr=$(wc -l $f | awk '{ print $1 }')
+    echo "\n$f, nrow=$nr, ncol=$nc"
+    ## TODO: see comments in head_col
+    if [ $nc -le 10 ]; then
+      scr="{ out=\$1; for (i=2; i<=10; i++) { out=out\" \"\$i }; print out }"
+    else
+      scr="{ out=\$1; for (i=2; i<=10; i++) { out=out\" \"\$i }; print out\" ... \"\$$nc }"
+    fi
+    head -n $lines $f | awk "$scr"
+    if [ $nr -gt $lines ]; then
+      echo "..."
+      echo "..."
+      echo "..."
+      tail -n $lines $f | awk "$scr"
+    fi
+  done
+}
+export -f see_col
+
+# HEAD_COL & TAIL_COL
+#-------------------------------------------------------------------------------
+# What: Show first/last rows and cols of a file, i.e., just first/last few
+#       rows and first/last few columns (useful when a file is very big)
+# Who: Gregor Gorjanc
+# When:
+#  * 2013-12 Initial version
+#-------------------------------------------------------------------------------
+
+head_col()
+{
+  ## $@ = file names
+  ## TODO: can we make no of cols an option?
+  ## TODO: delimiter as an option
+  ## TODO: combine {head,tail,see}_col as most code is the same
+  local nc
+  for f in $@; do
+    nc=$(head -n 1 $f | awk '{ print NF }')
+    nr=$(wc -l $f | awk '{ print $1 }')
+    echo "\n$f, nrow=$nr, ncol=$nc"
+    if [ $nc -le 10 ]; then
+      scr="{ out=\$1; for (i=2; i<=10; i++) { out=out\" \"\$i }; print out }"
+    else
+      scr="{ out=\$1; for (i=2; i<=10; i++) { out=out\" \"\$i }; print out\" ... \"\$$nc }"
+    fi
+    head $f | awk "$scr"
+  done
+}
+export -f head_col
+
+tail_col()
+{
+  ## $@ = file names
+  local nc
+  for f in $@; do
+    nc=$(head -n 1 $f | awk '{ print NF }')
+    nr=$(wc -l $f | awk '{ print $1 }')
+    echo "\n$f, nrow=$nr, ncol=$nc"
+    ## TODO: see above comments in head_col
+    if [ $nc -le 10 ]; then
+      scr="{ out=\$1; for (i=2; i<=10; i++) { out=out\" \"\$i }; print out }"
+    else
+      scr="{ out=\$1; for (i=2; i<=10; i++) { out=out\" \"\$i }; print out\" ... \"\$$nc }"
+    fi
+    tail $f | awk "$scr"
+  done
+}
+export -f tail_col