analog: sane printing of very small and negative values

diff --git a/output/analog.c b/output/analog.c
index 3049ba738a78eb3325b3c0c33b2578b9e49847e8..d1fd7be6b17b2924ab72f49d761019d3f52f83ef 100644 (file)
--- a/output/analog.c
+++ b/output/analog.c
@@ -63,21 +63,27 @@ static int init(struct sr_output *o)
 
 static void si_printf(float value, GString *out, char *unitstr)
 {
+       float v;
 
-       if (value > 1000000000L)
-               g_string_append_printf(out, "%f G%s", value / 1000000000L, unitstr);
-       else if (value > 1000000)
-               g_string_append_printf(out, "%f M%s", value / 1000000, unitstr);
-       else if (value > 1000)
-               g_string_append_printf(out, "%f k%s", value / 1000, unitstr);
-       else if (value < 0.000000000001)
-               g_string_append_printf(out, "%f p%s", value * 1000000000000, unitstr);
-       else if (value < 0.000000001)
-               g_string_append_printf(out, "%f n%s", value * 1000000000, unitstr);
-       else if (value < 0.000001)
-               g_string_append_printf(out, "%f u%s", value * 1000000, unitstr);
-       else if (value < 0.001)
-               g_string_append_printf(out, "%f m%s", value * 1000, unitstr);
+       if (signbit(value))
+               v = -(value);
+       else
+               v = value;
+
+       if (v < 1e-12 || v > 1e+12)
+               g_string_append_printf(out, "%f %s", value, unitstr);
+       else if (v > 1e+9)
+               g_string_append_printf(out, "%f G%s", value / 1e+9, unitstr);
+       else if (v > 1e+6)
+               g_string_append_printf(out, "%f M%s", value / 1e+6, unitstr);
+       else if (v > 1e+3)
+               g_string_append_printf(out, "%f k%s", value / 1e+3, unitstr);
+       else if (v < 1e-9)
+               g_string_append_printf(out, "%f n%s", value * 1e+9, unitstr);
+       else if (v < 1e-6)
+               g_string_append_printf(out, "%f u%s", value * 1e+6, unitstr);
+       else if (v < 1e-3)
+               g_string_append_printf(out, "%f m%s", value * 1e+3, unitstr);
        else
                g_string_append_printf(out, "%f %s", value, unitstr);