Plot won't show line

Question

Loraine Luceñara 2019-7-25

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/473498-plot-won-t-show-line

回答： Vinod 2019-7-25

I've been trying to plot a chart on thingspeak. but the line won't seem to appear. How do I make the line appear?

I've tried to change the line to a dashed line, I've also tried to varying the linewidth but all it got me were much bigger markers. I've checked and all the arrays right size. If it helps, the timestamps array is a datetime array.

Here is all of my code:

% Channel ID to read data from 
readChannelID = 827912; 
% Temperature Field ID 
TemperatureFieldID = 1; 
% Wind speed Field ID 
HumidityFieldID = 4; 
% Channel Read API Key   
% If your channel is private, then enter the read API 
% Key between the '' below:   
readAPIKey = 'CZD7YSPVMXAAI188'; 
% Read Data. Learn more about the thingSpeakRead function by 
% going to the Documentation tab on the right side pane of this page. 
[data, timeStamps] = thingSpeakRead(readChannelID, 'Fields',[TemperatureFieldID HumidityFieldID], ...
                                                           'NumPoints', 300, ...
                                                           'ReadKey', readAPIKey);
% Extract the temperature data from the first column
temperatureData = data(:, 1);
% Extract the windspeed data from the second column
HumidityData = data(:, 2);
% Visualize Data
yyaxis left
plot(timeStamps, temperatureData,'mo-',...
    'LineWidth',2,...
    'MarkerEdgeColor','k',...
    'MarkerFaceColor',[.49 1 .63],...
    'MarkerSize',5);
ylabel('Temperature');
hold on;
yyaxis right
plot(timeStamps, HumidityData, '--mo',...
    'LineWidth',2,...
    'MarkerEdgeColor','k',...
    'MarkerFaceColor','b',...
    'MarkerSize',5);
ylabel('Humdity');