Sense hat in Fahrenheit

[chefdave]

I know Celsius is a better way to display temperature, but unfortunately here in the US we don't "get it".
Is there a way to make the Sense Hat display Temperature in Fahrenheit ?

[scotty101]

Yep just convert it.

Code: Select all

temp = ((temp/5)*9)+32

[andyk1]

Is there any way anyone can show me a line of code that uses this formula. I have searched and can not find a usable line of code for this. You can't just enter that into code and not run into errors.

[vetzki]

you could use something like this:

Code: Select all

def tofahrenheit(celsius):
    return( (celsius/5*9)+32 )

temp = tofahrenheit(sense.get_temperature())
print(temp)

[jahboater]

Is there any way anyone can show me a line of code that uses this formula. I have searched and can not find a usable line of code for this. You can't just enter that into code and not run into errors.

You most definitely can! Define "code"? What language?
You have been given some Python which is a very popular language for the purpose. I suspect you really mean "bash" the command interpreter (shell), in which case enclose the expression in (( and )).

The Pi and the sense hat are all about education.
So assuming you are using Python, try to modify the program (likely a .py) file, using the code given.
It should be really simple, and you will find it very satisfying when it works.
You will learn a lot which is what its all about!
Edit the Python file with nano.

[andyk1]

I suppose I should have been more clear. Yes writing in python 3.5.2
Trying to write for the Raspberry Pi Sensor Hat.

I manage to experiment and came up with the following:

t = sense.get_temperature() * 9/5 + 32
#or t = sense.get_temperature() * 1.8 +32

Both worked for my needs.

One other issue I am having is changing the color of the display... not background to a color say from:

-15 F to 65 F to be blue
66F to 85F to be green
86F to 120F to be red

On the sense-had display. I manage to get two colors to work, green and red but seems my code cancels out the colder blue code.

[bensimmo]

We would need your code for that.

copy and paste it all in code brackets faq.php?mode=bbcode#f2r1

personally if not at the command line then leafpad that RPF put in is much easier than nano.

[scotty101]

One other issue I am having is changing the color of the display... not background to a color say from:

-15 F to 65 F to be blue
66F to 85F to be green
86F to 120F to be red

On the sense-had display. I manage to get two colors to work, green and red but seems my code cancels out the colder blue code.

Be sure that you use the correct IF..ELIF..ELSE syntax in python.
For example (Modify for your own requirements)

Code: Select all

if temp <= 65:
   displayBlue()
elif temp > 65 and temp <=85 :
   displayGreen()
else:
   displayRed()

[andyk1]

Let me try this again...

I will try and answer all your questions but first thank you all. For me as someone said would be easier to show you what I have so far. Yes am just learning.

Code: Select all

# Project By Andy to create temp, hum, press,  wind,  rain, soil, uv , security cam's and other sensor.
from sense_hat import SenseHat
sense = SenseHat()
sense.set_rotation(180)

while True:
    t =  sense.get_temperature()  *  9/5  +  32 # changed to Fahrenheit. Works
#  t =  sense.get_temperature() *  1.8 + 32;    another way to read F temp
    p = sense.get_pressure()
    h = sense.get_humidity()

    t = round(t, 1)
    p = round(p, 1)
    h = round(h, 1)

#    if t > -15.0 and t < 64.9:  # can't get to read 
#      tc = [0, 0, 100]  # Blue
#    else:
#      tc = [0, 100, 0]  # Green

    if t > 65.0 and t < 84.9:
        tc = [0, 100, 0]  # Green
    else:
        tc = [100, 0, 0]  # Red

#     if h > 85.0 and h < 120.0:  can't get to read 
#        tc = [100, 0, 0]  # red
#      else:                                    can't get to read
#         tc = [100, 0, 0]  # red


#  msg = "T={0} P={0} H={0}"  .format ( t,p,h )
    msg = "T=%s P=%s H=%s"% (t , p, h)
#    sense.show_message(msg, scroll_speed=0.05, text_colour=[0,0,0], back_colour=bg)
    sense.show_message(msg, scroll_speed=0.07, text_colour=tc) # bg=background color

# todo. setup other sensors
# todo. setup day-night brightness
# todo .setuo to show on monitor also

hope I read this right.

As you can see parts of it works and parts don't. Not sure why I can't get this.

[DougieLawson]

Edit your post and everywhere you've got [quote] change it to [code] and everywhere you've got [/quote] change it to [/code]

That will fix the ugly code formatting.

[andyk1]

Thanks DougieLawson I did that

[Paeryn]

Code: Select all

#    if t > -15.0 and t < 64.9:  # can't get to read 
#      tc = [0, 0, 100]  # Blue
#    else:
#      tc = [0, 100, 0]  # Green

    if t > 65.0 and t < 84.9:
        tc = [0, 100, 0]  # Green
    else:
        tc = [100, 0, 0]  # Red

#     if h > 85.0 and h < 120.0:  can't get to read 
#        tc = [100, 0, 0]  # red
#      else:                                    can't get to read
#         tc = [100, 0, 0]  # red

I assume that should be t in the final commented out if statement, not h.
If they were not commented out then only the final if statement would take effect (either it's true or false section), it would overwrite whatever value was set in either of the other two before it.

If you want absolutely those ranges then something like

Code: Select all

if -15 <= t <= 65:
  tc = [0, 0, 100] # Blue
elif 65 < t <= 85:
  tc = [0, 100, 0] # Green
elif 85 < t <= 120:
  tc = [100, 0, 0] # Red
else:
  tc = [100, 100, 100] # White

Here I've set tc to white if t is outside the specified range (to make sure it's set to something).

If you want always less than or equal to 65 to be blue, and always above 85 to be red with anything in between to be green then

Code: Select all

if t <= 65:
  tc = [0, 0, 100] # Blue
elif t <= 85:
  tc = [0, 100, 0] # Green
else:
  tc = [100, 0, 0] # Red

[bensimmo]

It looks like you need to alter your If/Else into the format given above.

e.g.

Code: Select all

if temperature < 65:
   temp_background_colour = [0, 0, 100]
elif temperature > 85 :
   temp_background_colour = [100, 0, 0] 
else:
   temp_background_colour = [0, 100, 0]

Which check for cold so blue, hot so red and anything else must be good so green

[bensimmo]

oh and while you're at ti, you can test your code here quickly, https://trinket.io/sense-hat
you may need to put a sleep into your while loop?

[andyk1]

Took all of your advice... thanks to everyone. Could not get some of your code to work for my purposes but trial and error I got this.

Code: Select all

from sense_hat import SenseHat
sense = SenseHat()
sense.set_rotation(180)

while True:
    t =  sense.get_temperature()  *  1.8  +  32;
    p = sense.get_pressure()
    h = sense.get_humidity()

    t = round(t, 1)
    p = round(p, 1)
    h = round(h, 1)

    if t <= 65:
      tc = [0, 0, 100] # Blue
    elif t <= 80:
      tc = [0, 100, 0] # Green
    else:
      tc = [100, 0, 0] # Red

    msg = "T=%s P=%s H=%s"% (t , p, h)
    sense.show_message(msg, scroll_speed=0.07, text_colour=tc) # bc=background color

I simplified it and does work.

Can someone show me how to print this to the monitor and sense-hat at the same time please? The print command doesn't work for me.

[scotty101]

Can someone show me how to print this to the monitor and sense-hat at the same time please? The print command doesn't work for me.

What about the print command doesn't work? Where do you expect the text to be displayed?

Are you running your program from the command line or from an IDE like IDLE?

[andyk1]

What about the print command doesn't work? Where do you expect the text to be displayed?

Are you running your program from the command line or from an IDE like IDLE?

I am using IDLE 3 Python 3.

What I am trying to do is have it display on the Pi sensor-hat and the Display monitor I have hooked up to the Rpi 3b via hdmi of course. Not sure why it does display on the sensor-hat but does not print to screen. Blank.
I am not at the terminal window so can't post the code. will in the morning. the code is actually a few posts up with the line:

print(t,p,h)

At the very bottom. No error code. No print to screen.

Need a cheat sheet for python 3 structure . Google is no help.

[scotty101]

Try the following

1. Open a instance of LXTerminal from the Raspberry Pi Menu
2. Type `python3`
3. At the python prompt type `print("Hello World")`
4. "Hello World" should be shown on the screen.
5. Type `quit()` to exit the python prompt.

The output of print will only be shown on a command prompt or similar terminal output. It won't appear as a popup or dialog on the screen for example.
Since you are using IDLE, the output of print should show up in the IDLE window that is probably called "Python 3.4.3 Shell"