Analysis
I was given two activities with subparts I was supposed to complete for analysis of data collected from 2019-2021.
Time Series Analysis
My task was to examine the data and see if there are differences in Phycocyanin (PC), Chlorophyll-a (Chla), and PC/Chla over time.
I examined the variability in PC, Chla, and PC/Chla over the course of the individual summers, as well as between each year.
I also examined the comparable data sampled to the continuous data collection buoy on Lake Mendota.
Spatial Analysis
My task was to examine the data to see if there were spatial differences in Phycocyanin (PC), Chlorogphyll-a (Chla), and PC/Chla in the different grid boxes used for sampling (Grids 1 --> 35).
I examined the differences between littoral and pelagic zones.
I also examined if there were variable difference between two different sides of the lake (the inlet and outlet).
Matlab
To do the analysis of hundreds of lines of collected data, I learned the programming system Matlab.
Here are some of the commands I took note of:
General Commands
pwd - present working directory
ls - opens programs (list of what is in the working directory)
% - comments
; - used after command to make it silent
x[ ] - used fro vectors (#s only) row vector
y=x' - makes vector column
mat= - matrix(ex: [123; 732; -123])
ones - gives you ones in the matrix ones
zeros - gives you zeros in the matrix zero
NaN - missing data (Not a Number)
' ' - empty char array
f=[d d] - concatenation
array - pure # array (ex: a=[1 2 3])
data structure - cell array (ex: a{ 1 'C' 'letus' [1 2]})
help ____ - if you write the command after, it will tell you what the command is
eval ( ) - evaluated if there are numbers
clf - clears figure (ex: figure(1): clf)
~ - NaN
strcmp - compares string data
{: , 4} - shows everything on data column 4
cd - change directory
control p - previous command (keeping hitting control p to keep going through previous commands) (if you write something ' ' then control p it finds the previous command that has the same first letters or word)
control c - stops the program
& - and
| - or
Mathematical Commands
* - multiplication
mat. * mat2 - element wise multiplication
mat * mat2 - normal matrix multiplication
sin(x) - sin of x
x.^2 - squaring
sqrt(#) - square root
std - standard deviation
mean - mean value
Side Notes
indent 3 spaces for readability and logic
Graphing Commands
Naming:
title('something...') - for titling figures
xlabel(' ') - x axis title
ylabel(' ') - y axis title
zlabel(' ') - z axis title
Commands for Altercation:
grid on - turns the grid on in a figure
get(gca) - gets current axis
get(phandle(l) - shows all properties of line(l)
set(gca) - shows all the commands you can do within your graphs
Markers:
':' - solid line
'-' - solid line
'--' - dash line
'-.' dash dotted line
'o' - O
'+' - +
'*' - *
'.' - .
'-' - -
'l' - i
's' - square shape
'd' - diamond shape
'^' - triangle (point facing upwards)
'>' - triangle (point facing right)
'<' - triangle (point facing left)
'p' - star shape
'h' - hexagram shape
'x' - x
Example of the Analyzed Data
Time Versus Chlorophyll-a
There are 35 different lines representing the 35 different grids. The lines show the change of Chlorophyll-a present within Lake Mendota during the summer of 2021.
Average of Chla by Year (2019-2021)
Here is the average of Chlorophyll-a within grids 1-35 over the years (2019-2021)
Chlorophyll-a versus Distance from Yahara River inlet
This graph shows the average of the grids on the same row going from the inlet (Yahara River) to the outlet.