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version 1.1.0, 2020-04-29
- calc_b():					added a "method" parameter, which allows the user to use a linear regression of log10 values rather than the default nonlinear regression, if desired.
- plot_pcrit():			allows plotting of just the MO2 v PO2 if Pcrit cannot be calculated.
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version 1.0.2, 2020-01-24
- import_presens():		fixes an error when Fibox 4 files were exported with PreSens Datamanager.
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version 1.0.1, 2019-09-26
- import_firesting():		now can tolerate files with less than four channels calibrated.
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version 1.0.0, 2019-05-24
- calc_pcrit():			new function: Calculate Pcrit (hypoxia tolerance)
- plot_pcrit():			new function: Plot Pcrit (hypoxia tolerance)
- calc_b():			output changed from a numeric value for b to a list of 1. the b value and 2. a vector of b0 values
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version 0.7.0, 2018-08-12
- make_bins():			new function: Make time bins for MO2 calculations.
- calc_b():			improved the ability to converge on the b value.
- calc_MO2():			fixed an issue where an error was returned if the bin_width dataframe had a 0 value.
- calc_b():			fixed an issue where the returned value was incorrect.
- import_firesting():		fixed an issue with the example.
- guess_TA():			fixed an issue where an error message would improperly say salinity was outside of bounds when temperature was outside of bounds.
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version 0.6.0, 2018-01-23
- import_presens():		added support for PreSens SDR SensorDish Reader txt files
- calc_MO2():			added support to enter a data frame as an argument for the "bin width" parameter
- calc_MO2():			fixed an issue where an error would be returned if an entire bin was full of O2 = NA
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version 0.5.0, 2017-11-01
- import_firesting():		now supports "Firesting Logger" software and 1st generation FireStingO2 meter
- Q10():			option added to return an nls object with the model fit if vectors are provided
- Q10():			fixed a bug where the returned value was 1 when the first two elements of T_vec were identical
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version 0.4.0, 2017-05-27
- calc_MO2():			parameter added: "pH" which allows pH data to be summarized along with oxygen and duration data for each bin
- calc_MO2():			parameter added: "time" to include time mean and range in output
- Q10():			added new functionality allowing a vector of rate and temperature values to be input to return the best fitting Q10 value
- calc_MO2():     		columns MEAN_DURATION, MEAN_O2, and MEAN_PH were renamed to DUR_MEAN, O2_MEAN, and PH_MEAN, respectively
- calc_MO2():     		the DUR_RANGE column in the returned data frame is no longer rounded
- calc_MO2():     		"bad" data identified by the parameter "good_data" now split their bin so that linear regressions are not fit through data that contain bad observations in the middle
- conv_o2():			added support for "volumes_percent"
- conv_nh4():			conv_NH4() was renamed and includes support for "mg_NH3" and "umol_NH3"
- predict_nh3():		predict_NH4() was renamed and now returns a list of NH3, NH4, and TAN
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version 0.3.1, 2016-12-31
- calc_MO2():			parameter added: "good_data" which allows identified O2 observations to be excluded from analyses
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version 0.3.0, 2016-11-29
- calc_b():			new function: Calculate the metabolic scaling coefficient, b
- calc_MO2():			new function: Calculate metabolic rate
- conv_resp_unit():		new function: Convert units related to respirometry
- import_firesting():		new function: Import data from a FireSting O2 transmitter
- conv_o2():			added support for ug_per_l and ug_per_kg
- flush_o2():			now returns just the missing value(s) rather than the missing value(s) within a list
- flush_water():		now returns just the missing value(s) rather than the missing value(s) within a list
- flush_water():		now gives a meaningful error message when parameters have a length >1 and plot = TRUE
- Q10():			now returns just the missing value(s) rather than the missing value(s) within a list
- scale_MO2():			now returns just the missing value(s) rather than the missing value(s) within a list
- import_presens():		improved efficiency
- import_witrox():		improved efficiency
- predict_pH():			improved efficiency
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version 0.2.0, 2016-10-07
- closed():			new function: Closed respirometry
- import_presens():		new function: Import data from a PreSens O2 transmitter
- import_witrox():		new function: Import data from a Loligo Systems Witrox transmitter
- scale_MO2():			new function: Scale metabolic rate by size
- conv_o2():			added support for mmol_per_l and mmol_per_kg
- flush_o2():			added support for calculating any parameter from the others, not just calculating final O2.
- mean_pH():			returns an NA rather than error when pH = NULL
- co2_*.R():			improved documentation
- flush_water():		improved documentation
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version 0.1.2, 2016-09-02
- guess_TA():			now allows calculations if salinity is <= 5 psu outside the bounds, but with a warning.
- guess_TA():			fixed a bug where an error occurred if any NAs were provided
- predict_pH():			fixed a bug where an error occurred if any NAs were provided
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version 0.1.1, 2016-08-23
- predict_pH():			fixed a bug where a single NA was returned if any NAs were provided
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version 0.1.0, 2016-08-22
- co2_add():			new function
- co2_flush():			new function
- co2_rate():			new function
- conv_NH4():			new function
- conv_o2():			new function
- correct_bubble():		new function
- flush_carb():			new function
- flush_o2():			new function
- flush_water():		new function
- goal_flush_pH():		new function
- guess_TA():			new function
- guess_when():			new function
- max_MO2():			new function
- mean_pH():			new function
- min_flow():			new function
- peri_pump():			new function
- predict_NH4():		new function
- predict_pH():			new function
- Q10():			new function
- RQ():				new function
