Sprintf not inserting float values

Sprintf is not properly inserting float variables into the desired output string. My code is simple:

float thp_data[3];  
char output[256];
thp_data[0] = 1.234
thp_data[1] = 1.234
thp_data[2] = 1.234
sprintf(output, "Humidity: %.2f, Pressure: %.2f, Temperature: %.2f\r\n", thp_data[1], thp_data[2], thp_data[0]);

produces the following string in output:

Humidity: %.2f, Pressure: %.2f, Temperature: %.2f

Any ideas on how to fix this?

Floating point output for printf is disabled by default to reduce flash size. This a faq, search for ‚minimal printf‘ or look here: Mbed minimal-printf not padding format