TLDR; Stick with the CG50 unless you find the new UI compelling

Released about six months ago, I finally picked up a Casio fx-CG100. Physically, it is a very pretty device, and the buttons feel great. I was excited to benchmark it and put it through my torture tests, but was pretty shocked by the results. It is actually a touch slower than the CG50 on all of my benchmarks, and uses the exact same algorithms as the CG50. That means that the gains in precision that we've seen with the fx-991CW do not carry over to the new flagship graphing calculator.

The UI has some welcome improvements, especially if you do a lot of linear algebra. On the main calculate page, defining vectors and matricies are only one button press away instead of digging through menus. I personally find the Catalog and Tools method of accessing functions to be a more intuitive method than the F-buttons, but your mileage may vary.

The biggest difference between the CG100 and the CG50 is that the CG100 lacks the ability to install additional programs. That means no khiCAS, and you're stuck with only what comes preinstalled. If I wasn't a collector/enthusiast, I'd strongly recommend giving this particular calculator a hard pass. As it is, exploring the unique UI and enjoying the physical attributes of the calculator make it worth it to me, and I'm happy to have it in my arsenal.

The last three pens that I picked up were Nahvalurs, including a couple of big, chunky Nautili. I love the heft of those pens, and when I first pulled this M205 out of the box I was shocked by how tiny and light it is. At first I would have described it as feeling insubstantial, but after spending a few hours with it, I'd have to say that it is a delicate pen. Not fragile, but delicate. It is such a lovely writer!

I have it inked up with Anderillium Roseate Spoonbill Pink.

I have a couple of Lamy 2000s, one inked with Diamine Wild Strawberry and the other one with Sailor Manyo Yamabuki. It takes me a couple of months to write them dry, after which I give them a good cleaning and ink them back up again.

The Diamine Wild Strawberry has been fine, but about a month into my latest fill of the Sailor Manyo Yamabuki it started coming out as a distinctly dark brown. I took the nib and feeder out to give it a scrubbing, and there was a build up of residue on the nib that took some scrubbing to get off. The ink behaved fine for the rest of the day, but has already started to darken again after about 72 hours.

Should I dump what's left in the reservoir? Try a different ink? Or is this normal for Yamabuki?

This is the calculator that my father bought for his senior year of high school in 1974. He showed it to me when I was four and I remember being amazed that a little box could add and subtract, captivated by the tiny red numbers. It was a few months later that he brought home our first computer, a Texas Instruments TI-99/4A, and I was again smitten. So much of the trajectory of my life can be traced back to those two objects.

When I opened the unit up I was not too terribly surprised to see a set of four AA batteries from the late 80's still installed, but I was very lucky that they hadn't leaked. I popped a new set in and it powered on with no issues. I played with it for a moment, the first time I had ever pushed the buttons on it, and placed it in the closet. I know it will be the perfect phylactery when I become a lich.

Originally posted by @[email protected] to [email protected]

I finally got around to picking up a Majohn A2, and it has been a phenomenal writing experience! For an extra fine nib, it is wet and smooth, just the slightest bit of feedback from the paper. While the action of the push button has a noticeable hitch in it, it is still a very satisfying frob to play with. The size is perfect for the weight, and the clip doesn't get in the way of the way that I hold it. The only thing that sucks about it is that now I want one in black that I can fill with Platinum Carbon Black and a dark blue one to fill with Diamine Midnight. Many thanks to @[email protected] for the review that sparked my desire!

Nahvalur Original Plus in Matira Quartz with a Medium Steel nib, and inked up with Diamine Frosted Orchid. Absolutely stunning combination! Bonus definition of the word chatoyant.

I just got an email from Casio Education saying that the next graphing calculator is coming next summer, and that prototypes will be shown off at the National Council of Teachers of Match Expo. I'm in the Chicago area, but tickets for non-members are way outside of my discretionary budget. If anybody is going, you'll have to fill us in!

The TI-nspire CX CAS was my first calculator with in integrated CAS, and it was a revelation! I was amazed that a handheld calculator could do symbolic logic, even though the technology goes back to the late '90s. I just never knew that it was a thing. The UI and software for the CX is almost identical to the CX II, though the CX II is more than twice as fast. The touchpad in the middle of the directional button was also improved quite a bit on the CX II. I still use this guy quite a bit, just because it is a special calculator to me. The CAS is not as full-featured as that on either the HP Prime or the Casio fx-CG500, but still powerful as hell. The CX also does not have the third-party support that the TI-89 Titanium has, but is many times faster than it and has the benefit of using a UI that was designed for its form factor.

The pen is an Asvine V200 Titanium M.

My new Asvine V200 Titanium with a medium nib arrived yesterday. The vacuum filler is much smoother than any of my V126s, and on par with my TWSBI Vac 700R. I also picked up a 30 ml bottle of Diamine Earl Grey, but the number of fills I'll be able to get with this pen is limited by the section being too wide to fit in the mouth of the bottle. I need to get different ink? Oh no!

Calculator is a TI-nspire CX CAS, and was my first calculator with a built-in CAS.

My wife got me this Hongdian 1851 for Christmas last year, along with the astronaut pen holder. Since I keep it out on my desk, it is the pen that I reach for most often. It has the finest line of all of my pens and I keep it inked up with iroshizuku murasaki-shikibu, which is an incredibly close match to the body of the pen. It has a lot of feedback without being scratchy, and is great to write with.

The calculator is a Casio fx-260 Solar II, which Kristi also got me for Christmas some years ago. It's the calculator that I grab most often since it is the easiest to get to. It's my little Apocalypse Calculator since it has no battery and is solar powered only.

Sorry the angle is a little funky, but this is one of my two workhorses, the Casio BN-20. This guy gets used almost every day, and is my primary source of truth for my calendar and contacts. It was released in 1998 and has 2 MB of user memory. The spreadsheet function is pretty rudimentary, and the only function that I don't have a lot of experience with. The expense function is the best expense tool I've ever seen on an electronic organizer. I run Xubuntu on modern hardware and can sync the data using Casio PC Sync through Wine and with a USB to serial converter.

I finally completed my collection of all six colorways of the Asvine V126 fountain pen. All of them have Asvine medium nibs, and I've been delighted with how well all of them feel in the hand and lay down ink. I'm also mighty happy with the inks that I've paired them with, although the shimmer in the Heart of Gold means that I need to spend more time on maintenance than the others.

I've had this guy for about a 18 months and it is one of my favorites. It is slower than the HP Prime and the TI-nspire CX II CAS, but still blows the TI-89 Titanium out of the water as far as speed goes. The huge touchscreen gives it a unique UI that is easier to navigate than the TIs. I've found that this is the best of my collection for linear algebra, and it is the easiest of my CAS calculators to use.

Does anybody else find it odd that the HP Prime stashes the vector field plots in the Geometry app instead of the Advanced Graphing app?

My 30+ year-old Casio fx-7700G is the oldest calculator in my collection. It's a little worn, but still works and gets used! It's been a wonderful companion over the years.

Several new inks and two new pens over the last few days! The Pilot Metro I've had for a couple of weeks now, but had been using the stock black cartridge that came with it while the Diamine Emerald got lost in the mail for a few days. While waiting for the Emerald, I got impatient and bought a three-pack of Diamine Green/Black, Writer's Blood, and Midnight.

I also wanted to try a Japanese fine nib, so I ordered the Pilot Lightive. I'd been getting really curious about Chinese pens as well, and at $11 USD, the HongDian 525 seemed like a great experiment.

First, the inks. All four of them are beautiful, but after seeing the Emerald, the Green/Black seems a little lifeless. Green/Black is still a lovely color and fits in very well with the rest of the trio, but the Emerald is exactly what I was looking for in a green for right now. It's an added bonus that it matches the color of that Retro Pop so well! The Midnight and Writer's Blood are also stellar inks. I can see why the Writer's Blood is such a popular color.

The Pilot Lightive is a wonderful pen to write with. I can definitely see the difference between the German fine of the Lamy Safari and the Japanese fine of the Pilot. For as fine as it is, there is very little feedback and it just glides over the paper. I've been using it quite a bit over the last few days!

The HongDian just arrived about twenty minutes ago, but I'm quite pleased with it so far. It has the same width as the Pilot despite it being sold as an extra-fine. It has a lot of feedback, but it's not what I'd call scratchy. It just lets you know that the paper has some tooth. It's a heavy pen, weighing in more than the Metro, which is a physically larger pen. It also needs a bit heavier hand to get the ink flowing. My other pens just need the weight of the pen, but the HongDian needs the slightest bit of pressure at the start of a line.

I'm excited to keep writing with all of my new toys!

I absolutely love this calculator, with one important caveat: I will never do integrations with this machine except as a test. Its integration algorithm tips over at ridiculously low speeds when it comes to edge cases. I find that it adds to the Sharp's charm, but it definitely affects its usefulness. Aside from that, this nifty little guy has a few features that you can't find on other calculators, and is arguably the best one out there for statistics and tables.

First of all, those buttons labeled D1 through D3 on the top row? Those are this calculator's super power. Programmable Buttons! Let's say that you're in Matrix Mode, and you are doing a whole bunch of stuff with matrices A and B. Typically, to use matrix A it's a three button journey: MATH -> 0 MATRIX -> 0 matA. Instead, you can hit STO D1 and it will let you assign matA to the single button press of D1. Any function from any menu can be mapped to one of those three buttons, saving tons of button presses if you get into the habit of using them.

Most scientifics don't make it too difficult to do base-n calculations, but Sharps make it the easiest out of any manufacturer that I've tried. They are also the only one that supports pental in addition to the standard hex, decimal, octal, and binary. Honestly, I've never had any reason to use pental, but if you're doing something that requires it, this is the only way to go!

It doesn't have any stats features that the Casio fx-991EX or CW don't have, but it does have persistent memory. Anything that you pop into the statistics lists or tables are retained after the calculator is shut down. This is a huge win over the Casios which clear everything when you switch modes or power them off. If you're working with stable sets of data over a longer period of time, this is a lifesaver!

For tables, the Sharp is also a clear winner. When making a table from a function, both the Casios and the TIs have a static value for where x starts. The Casios will only compute 15 steps, while the TIs will continue to calculate as you scroll down through the values. The Sharps not only do rolling calculations going forward, but backwards as well. It's a nice feature to have if you use tables quite often.

Then there's the not so rosy stuff. The aforementioned integrations being the most egregious. It handles easy integrations as well as any other, but when it comes to edge cases it falls down in a light breeze. Take int(e^-x^, 0, A), for instance. Every non-CAS calculator will crap out as A increases in value, but some are far better than others. The new Casio fx-991CW can handle A all the way up to 2.55x10^9^. Even the Catiga CS-121 can get up to 1500 before it gets inaccurate. The Sharp EL-W516T? 16. It dies at 16. Says that the integral is greater than one. It's embarrassing!

The other place that it distinctly craps out in comparison to other flagship scientific calculators is its SHIFT+SOLVE function. It will only solve algebraic equations with a 0 on one side. It won't solve integrations or derivatives like the Casio, and even the TI 36X Pro can handle equations with x on either side of the equals sign. With the Sharp, you need to perform the algebra to get one side equal to 0 or it errors out.

Overall, it's a great device that gets a lot of use on my desk. You just need to be aware of where it is is weak, and be prepared for those inaccuracies.

I found this guy used on shopgoodwill.com for about $20 USD a few months ago. It was on my list of calculators to procure, but the going rate of $130 USD for a new one was way out of my range. I was ecstatic to find one in such great shape for a low price!
This is an amazing calculator with some glaring issues that make it more of a mixed bag than it could have been.

This is the last calculator produced by TI with the OS that was originally designed for the TI-92, TI's first calculator with a built-in CAS. The fact that it was written for a device with a full QWERTY keyboard is glaringly obvious. The UI has been crammed into a standard graphing calculator form factor in such a way that some key combinations can't be silk-screened on the keypad. Base 10 log is Green Diamond + 7, for example.

The other huge problem with it is the speed reflects when it was designed. This calculator was released in 2004, and has had no upgrades since. As such, it is ungodly slow to perform a lot of calculations. In most cases, it performs on par with the Casio fx-991EX, a calculator which costs 1/7 as much. Graphing speed is pretty close to the Casio CFX-9850G from the mid 90s. This thing is unbelievably slow compared to most currently available calculators.

On the other hand, with the software being as mature as it is, it is amazing. There are program packages for the TI-89 Titanium that have no rival on any other platform. EEPro and MEPro are both freely downloadable from TI and provide a suite of activities, functions, and references customized for electrical engineering and mechanical engineering, respectively.

I'm very happy with this machine, and it does get quite a bit of use in spite of its shortcomings.

I've spent a couple of months with this guy, buying it just after it was released in the US. I've long been a fan of the 991EX, and the CW is quite a different beast in terms of UI and capabilities.

First off, this thing is an absolute beast! It is the most accurate and precise calculator that I own by far. I knew when I put the fx-115ES Plus 2nd Edition through its paces and watched it soundly beat the 991EX that the CW was going to be a leap in capability, but I had no idea how large that leap would be. Take a look at arcsin(arccos(arctan(tan(cos(sin(9)))))-9 in degree mode, which should equal 0 but never will if your calculator is solving it arithmetically. most calculators will give an answer in the range of 1x10^-6^ to 1x10^-9^. The CW's answer is 7.5528x10^-18^, doubling the number of accurate digits!

Another mind blowing one is it's integration abilities. One of my favorite tests is int(e^-x, 0, A) and finding the value for A where the integration breaks. The value should approach 1 as A increases, but because the calculator's algorithm for integrating is not exact it will reach a value for A where the answer is wrong because it starts ignoring smaller values of x. Most of my calculators can make it to A being four digits long before they decide that the answer is either 0 or they declare an error. The CW gets all the way to 2.55x10^9^ before it craps out. I was astounded!

As for the UI, limiting each button to a single shifted function is a double-edged sword. It irks me that I need to dig through a menu to find some pretty basic things like integrations and derivatives. At the same time, I'm approaching 50 and my eyesight is not what it used to be. I don't need to take off my glasses and squint at the keys to see what they do. I wasn't sure what I'd think of the round keys, but they feel great in use. I'm also disappointed that they removed the ability to perform simultaneous equations with the : symbol, but it was a feature that not many people even knew about, let alone used regularly.

The only improvement that the CW let me down with is it still lacks persistent memory. It has a lovely spreadsheet function that is made useless by forgetting all of the entered data as soon as you change functions or turn it off. The same thing goes for data in lists or the statistical apps. This is not a calculator to take out into the field and use while gathering data. It really is the only thing that has kept the fx-991 series from being the perfect scientific calculator. It's still close enough to be really impressive!